diff mbox series

opkg: enable zstd support

Message ID 20220913123741.3416807-1-ecordonnier@snap.com
State Under Review
Headers show
Series opkg: enable zstd support | expand

Commit Message

Etienne Cordonnier Sept. 13, 2022, 12:37 p.m. UTC
This allows the use of zstd for opkg packages by using OPKGBUILDCMD:
OPKGBUILDCMD = "opkg-build -Z zstd"

Signed-off-by: Alex Feinman <afeinman@snap.com>
Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
---
 meta/recipes-devtools/opkg/opkg_0.6.0.bb | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Alex Stewart Sept. 13, 2022, 7:19 p.m. UTC | #1
ACK from me - apart from enabling zstd by default.

On 9/13/22 07:37, Etienne Cordonnier via lists.openembedded.org wrote:
> This allows the use of zstd for opkg packages by using OPKGBUILDCMD:
> OPKGBUILDCMD = "opkg-build -Z zstd"
>
> Signed-off-by: Alex Feinman <afeinman@snap.com>
> Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
> ---
>   meta/recipes-devtools/opkg/opkg_0.6.0.bb | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/meta/recipes-devtools/opkg/opkg_0.6.0.bb b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> index 7b351e8123..e38d9d6f3f 100644
> --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
>   target_localstatedir := "${localstatedir}"
>   OPKGLIBDIR ??= "${target_localstatedir}/lib"
>   
> -PACKAGECONFIG ??= "libsolv"
> +PACKAGECONFIG ??= "libsolv zstd"

Building in zstd support by default is a little suspect to me.

Unless I'm mistaken, OE-core will only build xz-compressed IPKs by 
default. So zstd support would be unnecessary for a distro integrator 
who just uses upstream OE-core.

For distros which use zstd compression in their packages, I think it 
would be more appropriate to overwrite the opkg PACKAGECONFIG in a 
.bbappend.

Is there something I'm not considering here?

>   
>   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>       gnupg gpgme libgpg-error,\
> @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>   PACKAGECONFIG[curl] = "--enable-curl,--disable-curl,curl"
>   PACKAGECONFIG[ssl-curl] = "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
>   PACKAGECONFIG[sha256] = "--enable-sha256,--disable-sha256"
> +PACKAGECONFIG[zstd] = "--enable-zstd,--disable-zstd,zstd"
>   PACKAGECONFIG[libsolv] = "--with-libsolv,--without-libsolv,libsolv"
>   
>   EXTRA_OECONF:class-native = "--localstatedir=/${@os.path.relpath('${localstatedir}', '${STAGING_DIR_NATIVE}')} --sysconfdir=/${@os.path.relpath('${sysconfdir}', '${STAGING_DIR_NATIVE}')}"
>
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Khem Raj Sept. 13, 2022, 7:42 p.m. UTC | #2
On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart <alex.stewart@ni.com> wrote:
>
> ACK from me - apart from enabling zstd by default.
>
> On 9/13/22 07:37, Etienne Cordonnier via lists.openembedded.org wrote:
> > This allows the use of zstd for opkg packages by using OPKGBUILDCMD:
> > OPKGBUILDCMD = "opkg-build -Z zstd"
> >
> > Signed-off-by: Alex Feinman <afeinman@snap.com>
> > Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
> > ---
> >   meta/recipes-devtools/opkg/opkg_0.6.0.bb | 3 ++-
> >   1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/meta/recipes-devtools/opkg/opkg_0.6.0.bb b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> > index 7b351e8123..e38d9d6f3f 100644
> > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
> >   target_localstatedir := "${localstatedir}"
> >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
> >
> > -PACKAGECONFIG ??= "libsolv"
> > +PACKAGECONFIG ??= "libsolv zstd"
>
> Building in zstd support by default is a little suspect to me.
>
> Unless I'm mistaken, OE-core will only build xz-compressed IPKs by
> default. So zstd support would be unnecessary for a distro integrator
> who just uses upstream OE-core.
>
> For distros which use zstd compression in their packages, I think it
> would be more appropriate to overwrite the opkg PACKAGECONFIG in a
> .bbappend.
>

This is perhaps fine. I do wonder if there is some performance
comparison data between xz and zstd compressed ipks
with opkg, it might help users on making this choice and also if we
should consider using
zstd by default at some point or not.

> Is there something I'm not considering here?
>
> >
> >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
> >       gnupg gpgme libgpg-error,\
> > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
> >   PACKAGECONFIG[curl] = "--enable-curl,--disable-curl,curl"
> >   PACKAGECONFIG[ssl-curl] = "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
> >   PACKAGECONFIG[sha256] = "--enable-sha256,--disable-sha256"
> > +PACKAGECONFIG[zstd] = "--enable-zstd,--disable-zstd,zstd"
> >   PACKAGECONFIG[libsolv] = "--with-libsolv,--without-libsolv,libsolv"
> >
> >   EXTRA_OECONF:class-native = "--localstatedir=/${@os.path.relpath('${localstatedir}', '${STAGING_DIR_NATIVE}')} --sysconfdir=/${@os.path.relpath('${sysconfdir}', '${STAGING_DIR_NATIVE}')}"
> >
> >
> >
>
> --
> Alex Stewart
> Software Engineer - NI Real-Time OS
> NI (National Instruments)
>
> alex.stewart@ni.com
>
>
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>
Alex Feinman Sept. 13, 2022, 8:24 p.m. UTC | #3
On Tue, Sep 13, 2022 at 1:20 PM Alex Feinman <afeinman@snap.com> wrote:

> I do have some numbers. When I was selling this change internally, I did a
> comparison on our internal build.
>
>           Combined write IPK times (Σ t do_package_write_ipk)
>
> xz         162m 35s
>
> gz         52m 13s
>
> zstd       33m 49s
>
> Compression rate for zstd was closer to xz than to gz but not as good as xz. For systems that have to cache packages on the device with limited storage xz might be a better option, but for the bulk of projects zstd is the best choice
>
> Additionally, zstd offers much faster decompression than xz so the rootfs build step that includes unpacking all of the ipks, takes 3m 58s with xz and 2m 44s with zstd.
>
> One other thing of note - if your build includes debug packages, some may be quite large. E.g. one of our components produces a 2.2 GB debug package (uncompressed). On large files xz requires a disproportionally large amount of time resulting in 15 minutes needed to simply write ipk for the abovementioned packages, whereas zstd took about 45 sec. For frequent tasks like bitbaking a single package this translates in a lot of saved time.
>
> Bottom line - I think making xz a default package compressor was not entirely thought through. gzip or zstd is what the default should be.
>
> One final note: I could not find a reasonable explanation for why opkg-tools require code changes to support a different compressor. BSD tar and GNU tar both can easily accept compressors that they have no idea about (via -I option) because all of them provide a unified command line interface for use in pipes. If this were done similar to tar, we could have used any compressor we wanted, including the multithreaded versions (zstdmt)
>
>
> On Tue, Sep 13, 2022 at 12:43 PM Khem Raj <raj.khem@gmail.com> wrote:
>
>> On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart <alex.stewart@ni.com>
>> wrote:
>> >
>> > ACK from me - apart from enabling zstd by default.
>> >
>> > On 9/13/22 07:37, Etienne Cordonnier via lists.openembedded.org wrote:
>> > > This allows the use of zstd for opkg packages by using OPKGBUILDCMD:
>> > > OPKGBUILDCMD = "opkg-build -Z zstd"
>> > >
>> > > Signed-off-by: Alex Feinman <afeinman@snap.com>
>> > > Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
>> > > ---
>> > >   meta/recipes-devtools/opkg/opkg_0.6.0.bb | 3 ++-
>> > >   1 file changed, 2 insertions(+), 1 deletion(-)
>> > >
>> > > diff --git a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> > > index 7b351e8123..e38d9d6f3f 100644
>> > > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> > > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> > > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
>> > >   target_localstatedir := "${localstatedir}"
>> > >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
>> > >
>> > > -PACKAGECONFIG ??= "libsolv"
>> > > +PACKAGECONFIG ??= "libsolv zstd"
>> >
>> > Building in zstd support by default is a little suspect to me.
>> >
>> > Unless I'm mistaken, OE-core will only build xz-compressed IPKs by
>> > default. So zstd support would be unnecessary for a distro integrator
>> > who just uses upstream OE-core.
>> >
>> > For distros which use zstd compression in their packages, I think it
>> > would be more appropriate to overwrite the opkg PACKAGECONFIG in a
>> > .bbappend.
>> >
>>
>> This is perhaps fine. I do wonder if there is some performance
>> comparison data between xz and zstd compressed ipks
>> with opkg, it might help users on making this choice and also if we
>> should consider using
>> zstd by default at some point or not.
>>
>> > Is there something I'm not considering here?
>> >
>> > >
>> > >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>> > >       gnupg gpgme libgpg-error,\
>> > > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>> > >   PACKAGECONFIG[curl] = "--enable-curl,--disable-curl,curl"
>> > >   PACKAGECONFIG[ssl-curl] =
>> "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
>> > >   PACKAGECONFIG[sha256] = "--enable-sha256,--disable-sha256"
>> > > +PACKAGECONFIG[zstd] = "--enable-zstd,--disable-zstd,zstd"
>> > >   PACKAGECONFIG[libsolv] = "--with-libsolv,--without-libsolv,libsolv"
>> > >
>> > >   EXTRA_OECONF:class-native =
>> "--localstatedir=/${@os.path.relpath('${localstatedir}',
>> '${STAGING_DIR_NATIVE}')} --sysconfdir=/${@os.path.relpath('${sysconfdir}',
>> '${STAGING_DIR_NATIVE}')}"
>> > >
>> > >
>> > >
>> >
>> > --
>> > Alex Stewart
>> > Software Engineer - NI Real-Time OS
>> > NI (National Instruments)
>> >
>> > alex.stewart@ni.com
>> >
>> >
>> > -=-=-=-=-=-=-=-=-=-=-=-
>> > Links: You receive all messages sent to this group.
>> > View/Reply Online (#170608):
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_message_170608&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=_VWADuvDS3QdSEYWTnh8wNH0lOxVHty18QZynvOtpcU&e=
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>> > -=-=-=-=-=-=-=-=-=-=-=-
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>
Khem Raj Sept. 13, 2022, 8:34 p.m. UTC | #4
Thanks for sharing, really appreciate it. How close were compression
rates in numbers ? I think some users might be sensitive to the
archive sizes, if its something
with in acceptable range, I do agree, zstd would be a better default these days.

On Tue, Sep 13, 2022 at 1:20 PM Alex Feinman <afeinman@snap.com> wrote:
>
> I do have some numbers. When I was selling this change internally, I did a comparison on our internal build.
>
>           Combined write IPK times (Σ t do_package_write_ipk)
>
> xz         162m 35s
>
> gz         52m 13s
>
> zstd       33m 49s
>
> Compression rate for zstd was closer to xz than to gz but not as good as xz. For systems that have to cache packages on the device with limited storage xz might be a better option, but for the bulk of projects zstd is the best choice
>
> Additionally, zstd offers much faster decompression than xz so the rootfs build step that includes unpacking all of the ipks, takes 3m 58s with xz and 2m 44s with zstd.
>
> One other thing of note - if your build includes debug packages, some may be quite large. E.g. one of our components produces a 2.2 GB debug package (uncompressed). On large files xz requires a disproportionally large amount of time resulting in 15 minutes needed to simply write ipk for the abovementioned packages, whereas zstd took about 45 sec. For frequent tasks like bitbaking a single package this translates in a lot of saved time.
>
> Bottom line - I think making xz a default package compressor was not entirely thought through. gzip or zstd is what the default should be.
>
> One final note: I could not find a reasonable explanation for why opkg-tools require code changes to support a different compressor. BSD tar and GNU tar both can easily accept compressors that they have no idea about (via -I option) because all of them provide a unified command line interface for use in pipes. If this were done similar to tar, we could have used any compressor we wanted, including the multithreaded versions (zstdmt)
>
>
> On Tue, Sep 13, 2022 at 12:43 PM Khem Raj <raj.khem@gmail.com> wrote:
>>
>> On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart <alex.stewart@ni.com> wrote:
>> >
>> > ACK from me - apart from enabling zstd by default.
>> >
>> > On 9/13/22 07:37, Etienne Cordonnier via lists.openembedded.org wrote:
>> > > This allows the use of zstd for opkg packages by using OPKGBUILDCMD:
>> > > OPKGBUILDCMD = "opkg-build -Z zstd"
>> > >
>> > > Signed-off-by: Alex Feinman <afeinman@snap.com>
>> > > Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
>> > > ---
>> > >   meta/recipes-devtools/opkg/opkg_0.6.0.bb | 3 ++-
>> > >   1 file changed, 2 insertions(+), 1 deletion(-)
>> > >
>> > > diff --git a/meta/recipes-devtools/opkg/opkg_0.6.0.bb b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> > > index 7b351e8123..e38d9d6f3f 100644
>> > > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> > > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> > > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
>> > >   target_localstatedir := "${localstatedir}"
>> > >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
>> > >
>> > > -PACKAGECONFIG ??= "libsolv"
>> > > +PACKAGECONFIG ??= "libsolv zstd"
>> >
>> > Building in zstd support by default is a little suspect to me.
>> >
>> > Unless I'm mistaken, OE-core will only build xz-compressed IPKs by
>> > default. So zstd support would be unnecessary for a distro integrator
>> > who just uses upstream OE-core.
>> >
>> > For distros which use zstd compression in their packages, I think it
>> > would be more appropriate to overwrite the opkg PACKAGECONFIG in a
>> > .bbappend.
>> >
>>
>> This is perhaps fine. I do wonder if there is some performance
>> comparison data between xz and zstd compressed ipks
>> with opkg, it might help users on making this choice and also if we
>> should consider using
>> zstd by default at some point or not.
>>
>> > Is there something I'm not considering here?
>> >
>> > >
>> > >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>> > >       gnupg gpgme libgpg-error,\
>> > > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>> > >   PACKAGECONFIG[curl] = "--enable-curl,--disable-curl,curl"
>> > >   PACKAGECONFIG[ssl-curl] = "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
>> > >   PACKAGECONFIG[sha256] = "--enable-sha256,--disable-sha256"
>> > > +PACKAGECONFIG[zstd] = "--enable-zstd,--disable-zstd,zstd"
>> > >   PACKAGECONFIG[libsolv] = "--with-libsolv,--without-libsolv,libsolv"
>> > >
>> > >   EXTRA_OECONF:class-native = "--localstatedir=/${@os.path.relpath('${localstatedir}', '${STAGING_DIR_NATIVE}')} --sysconfdir=/${@os.path.relpath('${sysconfdir}', '${STAGING_DIR_NATIVE}')}"
>> > >
>> > >
>> > >
>> >
>> > --
>> > Alex Stewart
>> > Software Engineer - NI Real-Time OS
>> > NI (National Instruments)
>> >
>> > alex.stewart@ni.com
>> >
>> >
>> > -=-=-=-=-=-=-=-=-=-=-=-
>> > Links: You receive all messages sent to this group.
>> > View/Reply Online (#170608): https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_message_170608&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=_VWADuvDS3QdSEYWTnh8wNH0lOxVHty18QZynvOtpcU&e=
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>> > -=-=-=-=-=-=-=-=-=-=-=-
>> >
Alex Stewart Sept. 13, 2022, 9:57 p.m. UTC | #5
On 9/13/22 15:20, Alex Feinman wrote:
> I do have some numbers. When I was selling this change internally, I 
> did a comparison on our internal build.
>            Combined write IPK times (Σ t do_package_write_ipk)
> xz         162m 35s
> gz         52m 13s
> zstd       33m 49s
> Compression rate for zstd was closer to xz than to gz but not as good 
> as xz. For systems that have to cache packages on the device with 
> limited storage xz might be a better option, but for the bulk of 
> projects zstd is the best choice
> Additionally, zstd offers much faster decompression than xz so the 
> rootfs build step that includes unpacking all of the ipks, takes 3m 
> 58s with xz and 2m 44s with zstd.
> One other thing of note - if your build includes debug packages, some 
> may be quite large. E.g. one of our components produces a 2.2 GB debug 
> package (uncompressed). On large files xz requires a disproportionally 
> large amount of time resulting in 15 minutes needed to simply write 
> ipk for the abovementioned packages, whereas zstd took about 45 sec. 
> For frequent tasks like bitbaking a single package this translates in 
> a lot of saved time.

Those are certainly compelling performance improvements. Assuming that 
the final data-segment size is within 5%-ish of xz, then I would agree 
with the rest of the thread that it should probably be the contemporary 
default.

And if we make it the default compressor for OE IPKs, then obviously my 
criticism in the original PR is satisfied.

> Bottom line - I think making xz a default package compressor was not 
> entirely thought through. gzip or zstd is what the default should be.

ZStandard support was only added to opkg last September [1]. Before 
that, xz was the new hotness that replaced gzip. :)

[1] 
https://git.yoctoproject.org/opkg/commit/?id=5dead419e94bce2e6b743ad786c1daec0e1aa294

> One final note: I could not find a reasonable explanation for why 
> opkg-tools require code changes to support a different compressor. BSD 
> tar and GNU tar both can easily accept compressors that they have no 
> idea about (via -I option) because all of them provide a unified 
> command line interface for use in pipes. If this were done similar to 
> tar, we could have used any compressor we wanted, including the 
> multithreaded versions (zstdmt)

Well, presumably IPK creation tools can only support the matrix of 
compression algorithms which your opkg binary can decompress. I suppose 
someone could try to implement a plugable compression module system for 
opkg. But given that nearly everyone uses opkg in an embedded context, 
I'm not sure it would get much use.

>
> On Tue, Sep 13, 2022 at 12:43 PM Khem Raj <raj.khem@gmail.com> wrote:
>
>     On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart
>     <alex.stewart@ni.com> wrote:
>     >
>     > ACK from me - apart from enabling zstd by default.
>     >
>     > On 9/13/22 07:37, Etienne Cordonnier via lists.openembedded.org
>     <https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_bxrNjvo$>
>     wrote:
>     > > This allows the use of zstd for opkg packages by using
>     OPKGBUILDCMD:
>     > > OPKGBUILDCMD = "opkg-build -Z zstd"
>     > >
>     > > Signed-off-by: Alex Feinman <afeinman@snap.com>
>     > > Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
>     > > ---
>     > >   meta/recipes-devtools/opkg/opkg_0.6.0.bb
>     <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>     | 3 ++-
>     > >   1 file changed, 2 insertions(+), 1 deletion(-)
>     > >
>     > > diff --git a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>     <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>     b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>     <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>     > > index 7b351e8123..e38d9d6f3f 100644
>     > > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>     <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>     > > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>     <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>     > > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
>     > >   target_localstatedir := "${localstatedir}"
>     > >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
>     > >
>     > > -PACKAGECONFIG ??= "libsolv"
>     > > +PACKAGECONFIG ??= "libsolv zstd"
>     >
>     > Building in zstd support by default is a little suspect to me.
>     >
>     > Unless I'm mistaken, OE-core will only build xz-compressed IPKs by
>     > default. So zstd support would be unnecessary for a distro
>     integrator
>     > who just uses upstream OE-core.
>     >
>     > For distros which use zstd compression in their packages, I think it
>     > would be more appropriate to overwrite the opkg PACKAGECONFIG in a
>     > .bbappend.
>     >
>
>     This is perhaps fine. I do wonder if there is some performance
>     comparison data between xz and zstd compressed ipks
>     with opkg, it might help users on making this choice and also if we
>     should consider using
>     zstd by default at some point or not.
>
>     > Is there something I'm not considering here?
>     >
>     > >
>     > >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>     > >       gnupg gpgme libgpg-error,\
>     > > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] =
>     "--enable-gpg,--disable-gpg,\
>     > >   PACKAGECONFIG[curl] = "--enable-curl,--disable-curl,curl"
>     > >   PACKAGECONFIG[ssl-curl] =
>     "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
>     > >   PACKAGECONFIG[sha256] = "--enable-sha256,--disable-sha256"
>     > > +PACKAGECONFIG[zstd] = "--enable-zstd,--disable-zstd,zstd"
>     > >   PACKAGECONFIG[libsolv] =
>     "--with-libsolv,--without-libsolv,libsolv"
>     > >
>     > >   EXTRA_OECONF:class-native =
>     "--localstatedir=/${@os.path.relpath('${localstatedir}',
>     '${STAGING_DIR_NATIVE}')}
>     --sysconfdir=/${@os.path.relpath('${sysconfdir}',
>     '${STAGING_DIR_NATIVE}')}"
>     > >
>     > >
>     > >
>     >
>     > --
>     > Alex Stewart
>     > Software Engineer - NI Real-Time OS
>     > NI (National Instruments)
>     >
>     > alex.stewart@ni.com
>     >
>     >
>     > -=-=-=-=-=-=-=-=-=-=-=-
>     > Links: You receive all messages sent to this group.
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>      [raj.khem@gmail.com]
>     > -=-=-=-=-=-=-=-=-=-=-=-
>     >
>
Etienne Cordonnier Sept. 14, 2022, 9:58 a.m. UTC | #6
I ran a build of core-image-full-cmdline using xz and zstd, using
pre-populated downloads and sstate-cache directories but with empty tmp
directory. Here are the numbers:
zstd:
bitbake core-image-full-cmdline took 2m52.768s (real), the resulting
directory tmp/deploy/ipk is 1.6GB big.
xz:
bitbake core-image-full-cmdline took 4m14.214s (real), the resulting
directory tmp/deploy/ipk/ is 996M big

So the build with xz is 47% slower (254/172) than with zstd for this
"incremental build" use-case.

See the 5 biggest packages, the difference in compression-ratio increases
with big files:
build$ ls -lh tmp-zstd/deploy/ipk/core2-64/ --sort=size | head -n5
total 1.6G
-rw-r--r-- 3 ecordonnier ecordonnier  331M Sep 14 10:39
gcc-dbg_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier  264M Sep 14 10:39
openssl-dbg_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier  113M Sep 14 10:39
openssl-ptest_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   47M Sep 14 10:39
binutils-dbg_2.39-r0_core2-64.ipk
build$ ls -lh tmp-xz/deploy/ipk/core2-64/ --sort=size | head -n5
total 963M
-rw-r--r-- 3 ecordonnier ecordonnier  214M Sep 14 10:44
gcc-dbg_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier  193M Sep 14 10:44
openssl-dbg_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   35M Sep 14 10:44
openssl-ptest_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   32M Sep 14 10:44
binutils-dbg_2.39-r0_core2-64.ipk
...

I think for use-cases where the size of the ipk packages matters, xz is
better. For use-cases where it does not matter (ipk packages not deployed),
build-time matters more than compression-ratio and zstd is better.

Regarding the enablement of zstd in opkg per default, I'll send a new
version of the patch without this line.
My thinking for enabling zstd per default in opkg was that zstd is already
enabled per default in libarchive's PACKAGECONFIG, and disabling zstd in
opkg's PACKAGECONFIG removes only a few lines of code from opkg (opkg uses
libarchive for doing the actual compression/decompression).

On Tue, Sep 13, 2022 at 11:57 PM Alex Stewart <alex.stewart@ni.com> wrote:

>
>
> On 9/13/22 15:20, Alex Feinman wrote:
> > I do have some numbers. When I was selling this change internally, I
> > did a comparison on our internal build.
> >            Combined write IPK times (Σ t do_package_write_ipk)
> > xz         162m 35s
> > gz         52m 13s
> > zstd       33m 49s
> > Compression rate for zstd was closer to xz than to gz but not as good
> > as xz. For systems that have to cache packages on the device with
> > limited storage xz might be a better option, but for the bulk of
> > projects zstd is the best choice
> > Additionally, zstd offers much faster decompression than xz so the
> > rootfs build step that includes unpacking all of the ipks, takes 3m
> > 58s with xz and 2m 44s with zstd.
> > One other thing of note - if your build includes debug packages, some
> > may be quite large. E.g. one of our components produces a 2.2 GB debug
> > package (uncompressed). On large files xz requires a disproportionally
> > large amount of time resulting in 15 minutes needed to simply write
> > ipk for the abovementioned packages, whereas zstd took about 45 sec.
> > For frequent tasks like bitbaking a single package this translates in
> > a lot of saved time.
>
> Those are certainly compelling performance improvements. Assuming that
> the final data-segment size is within 5%-ish of xz, then I would agree
> with the rest of the thread that it should probably be the contemporary
> default.
>
> And if we make it the default compressor for OE IPKs, then obviously my
> criticism in the original PR is satisfied.
>
> > Bottom line - I think making xz a default package compressor was not
> > entirely thought through. gzip or zstd is what the default should be.
>
> ZStandard support was only added to opkg last September [1]. Before
> that, xz was the new hotness that replaced gzip. :)
>
> [1]
>
> https://urldefense.proofpoint.com/v2/url?u=https-3A__git.yoctoproject.org_opkg_commit_-3Fid-3D5dead419e94bce2e6b743ad786c1daec0e1aa294&d=DwIDaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=AhkbNonVuMIGRfPx_Qj9TsyDLWdbBqarUzFxz3aALck&m=VG_fgpCGq8Zgu73KQP1wTtb1D1TZftNpXj8jGnouPtGIBYyLIZbG8F-85POUcVN7&s=Mwoq2kkjfZhto6J5OomduJ5Rhyg_oSe-dkjeltE4Ls8&e=
>
>
> > One final note: I could not find a reasonable explanation for why
> > opkg-tools require code changes to support a different compressor. BSD
> > tar and GNU tar both can easily accept compressors that they have no
> > idea about (via -I option) because all of them provide a unified
> > command line interface for use in pipes. If this were done similar to
> > tar, we could have used any compressor we wanted, including the
> > multithreaded versions (zstdmt)
>
> Well, presumably IPK creation tools can only support the matrix of
> compression algorithms which your opkg binary can decompress. I suppose
> someone could try to implement a plugable compression module system for
> opkg. But given that nearly everyone uses opkg in an embedded context,
> I'm not sure it would get much use.
>
> >
> > On Tue, Sep 13, 2022 at 12:43 PM Khem Raj <raj.khem@gmail.com> wrote:
> >
> >     On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart
> >     <alex.stewart@ni.com> wrote:
> >     >
> >     > ACK from me - apart from enabling zstd by default.
> >     >
> >     > On 9/13/22 07:37, Etienne Cordonnier via lists.openembedded.org
> >     <
> https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_bxrNjvo$
> >
> >     wrote:
> >     > > This allows the use of zstd for opkg packages by using
> >     OPKGBUILDCMD:
> >     > > OPKGBUILDCMD = "opkg-build -Z zstd"
> >     > >
> >     > > Signed-off-by: Alex Feinman <afeinman@snap.com>
> >     > > Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
> >     > > ---
> >     > >   meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >     <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> >     | 3 ++-
> >     > >   1 file changed, 2 insertions(+), 1 deletion(-)
> >     > >
> >     > > diff --git a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >     <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> >     b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >     <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> >     > > index 7b351e8123..e38d9d6f3f 100644
> >     > > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >     <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> >     > > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >     <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> >     > > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
> >     > >   target_localstatedir := "${localstatedir}"
> >     > >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
> >     > >
> >     > > -PACKAGECONFIG ??= "libsolv"
> >     > > +PACKAGECONFIG ??= "libsolv zstd"
> >     >
> >     > Building in zstd support by default is a little suspect to me.
> >     >
> >     > Unless I'm mistaken, OE-core will only build xz-compressed IPKs by
> >     > default. So zstd support would be unnecessary for a distro
> >     integrator
> >     > who just uses upstream OE-core.
> >     >
> >     > For distros which use zstd compression in their packages, I think
> it
> >     > would be more appropriate to overwrite the opkg PACKAGECONFIG in a
> >     > .bbappend.
> >     >
> >
> >     This is perhaps fine. I do wonder if there is some performance
> >     comparison data between xz and zstd compressed ipks
> >     with opkg, it might help users on making this choice and also if we
> >     should consider using
> >     zstd by default at some point or not.
> >
> >     > Is there something I'm not considering here?
> >     >
> >     > >
> >     > >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
> >     > >       gnupg gpgme libgpg-error,\
> >     > > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] =
> >     "--enable-gpg,--disable-gpg,\
> >     > >   PACKAGECONFIG[curl] = "--enable-curl,--disable-curl,curl"
> >     > >   PACKAGECONFIG[ssl-curl] =
> >     "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
> >     > >   PACKAGECONFIG[sha256] = "--enable-sha256,--disable-sha256"
> >     > > +PACKAGECONFIG[zstd] = "--enable-zstd,--disable-zstd,zstd"
> >     > >   PACKAGECONFIG[libsolv] =
> >     "--with-libsolv,--without-libsolv,libsolv"
> >     > >
> >     > >   EXTRA_OECONF:class-native =
> >     "--localstatedir=/${@os.path.relpath('${localstatedir}',
> >     '${STAGING_DIR_NATIVE}')}
> >     --sysconfdir=/${@os.path.relpath('${sysconfdir}',
> >     '${STAGING_DIR_NATIVE}')}"
> >     > >
> >     > >
> >     > >
> >     >
> >     > --
> >     > Alex Stewart
> >     > Software Engineer - NI Real-Time OS
> >     > NI (National Instruments)
> >     >
> >     > alex.stewart@ni.com
> >     >
> >     >
> >     > -=-=-=-=-=-=-=-=-=-=-=-
> >     > Links: You receive all messages sent to this group.
> >     > View/Reply Online (#170608):
> >
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> >     <
> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_message_170608&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=_VWADuvDS3QdSEYWTnh8wNH0lOxVHty18QZynvOtpcU&e=
> >
> >
> >     > Mute This Topic:
> >
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> >
> >
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> >     <mailto:openembedded-core%2Bowner@lists.openembedded.org>
> >     > Unsubscribe:
> >
> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_unsub&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=PxAE_3yGzbSZ21-LHz_1r3gd2_STPoZcrYDeu9vd_GM&e=
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> >
> >      [raj.khem@gmail.com]
> >     > -=-=-=-=-=-=-=-=-=-=-=-
> >     >
> >
>
> --
> Alex Stewart
> Software Engineer - NI Real-Time OS
> NI (National Instruments)
>
> alex.stewart@ni.com
>
>
Etienne Cordonnier Sept. 14, 2022, 10:08 a.m. UTC | #7
Also note that zstd's default compression level is 3 per default (from a 1
to 19 scale). I did not test other compression levels.

On Wed, Sep 14, 2022 at 11:58 AM Etienne Cordonnier <
ecordonnier@snapchat.com> wrote:

> I ran a build of core-image-full-cmdline using xz and zstd, using
> pre-populated downloads and sstate-cache directories but with empty tmp
> directory. Here are the numbers:
> zstd:
> bitbake core-image-full-cmdline took 2m52.768s (real), the resulting
> directory tmp/deploy/ipk is 1.6GB big.
> xz:
> bitbake core-image-full-cmdline took 4m14.214s (real), the resulting
> directory tmp/deploy/ipk/ is 996M big
>
> So the build with xz is 47% slower (254/172) than with zstd for this
> "incremental build" use-case.
>
> See the 5 biggest packages, the difference in compression-ratio increases
> with big files:
> build$ ls -lh tmp-zstd/deploy/ipk/core2-64/ --sort=size | head -n5
> total 1.6G
> -rw-r--r-- 3 ecordonnier ecordonnier  331M Sep 14 10:39
> gcc-dbg_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier  264M Sep 14 10:39
> openssl-dbg_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier  113M Sep 14 10:39
> openssl-ptest_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   47M Sep 14 10:39
> binutils-dbg_2.39-r0_core2-64.ipk
> build$ ls -lh tmp-xz/deploy/ipk/core2-64/ --sort=size | head -n5
> total 963M
> -rw-r--r-- 3 ecordonnier ecordonnier  214M Sep 14 10:44
> gcc-dbg_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier  193M Sep 14 10:44
> openssl-dbg_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   35M Sep 14 10:44
> openssl-ptest_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   32M Sep 14 10:44
> binutils-dbg_2.39-r0_core2-64.ipk
> ...
>
> I think for use-cases where the size of the ipk packages matters, xz is
> better. For use-cases where it does not matter (ipk packages not deployed),
> build-time matters more than compression-ratio and zstd is better.
>
> Regarding the enablement of zstd in opkg per default, I'll send a new
> version of the patch without this line.
> My thinking for enabling zstd per default in opkg was that zstd is already
> enabled per default in libarchive's PACKAGECONFIG, and disabling zstd in
> opkg's PACKAGECONFIG removes only a few lines of code from opkg (opkg uses
> libarchive for doing the actual compression/decompression).
>
> On Tue, Sep 13, 2022 at 11:57 PM Alex Stewart <alex.stewart@ni.com> wrote:
>
>>
>>
>> On 9/13/22 15:20, Alex Feinman wrote:
>> > I do have some numbers. When I was selling this change internally, I
>> > did a comparison on our internal build.
>> >            Combined write IPK times (Σ t do_package_write_ipk)
>> > xz         162m 35s
>> > gz         52m 13s
>> > zstd       33m 49s
>> > Compression rate for zstd was closer to xz than to gz but not as good
>> > as xz. For systems that have to cache packages on the device with
>> > limited storage xz might be a better option, but for the bulk of
>> > projects zstd is the best choice
>> > Additionally, zstd offers much faster decompression than xz so the
>> > rootfs build step that includes unpacking all of the ipks, takes 3m
>> > 58s with xz and 2m 44s with zstd.
>> > One other thing of note - if your build includes debug packages, some
>> > may be quite large. E.g. one of our components produces a 2.2 GB debug
>> > package (uncompressed). On large files xz requires a disproportionally
>> > large amount of time resulting in 15 minutes needed to simply write
>> > ipk for the abovementioned packages, whereas zstd took about 45 sec.
>> > For frequent tasks like bitbaking a single package this translates in
>> > a lot of saved time.
>>
>> Those are certainly compelling performance improvements. Assuming that
>> the final data-segment size is within 5%-ish of xz, then I would agree
>> with the rest of the thread that it should probably be the contemporary
>> default.
>>
>> And if we make it the default compressor for OE IPKs, then obviously my
>> criticism in the original PR is satisfied.
>>
>> > Bottom line - I think making xz a default package compressor was not
>> > entirely thought through. gzip or zstd is what the default should be.
>>
>> ZStandard support was only added to opkg last September [1]. Before
>> that, xz was the new hotness that replaced gzip. :)
>>
>> [1]
>>
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__git.yoctoproject.org_opkg_commit_-3Fid-3D5dead419e94bce2e6b743ad786c1daec0e1aa294&d=DwIDaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=AhkbNonVuMIGRfPx_Qj9TsyDLWdbBqarUzFxz3aALck&m=VG_fgpCGq8Zgu73KQP1wTtb1D1TZftNpXj8jGnouPtGIBYyLIZbG8F-85POUcVN7&s=Mwoq2kkjfZhto6J5OomduJ5Rhyg_oSe-dkjeltE4Ls8&e=
>>
>>
>> > One final note: I could not find a reasonable explanation for why
>> > opkg-tools require code changes to support a different compressor. BSD
>> > tar and GNU tar both can easily accept compressors that they have no
>> > idea about (via -I option) because all of them provide a unified
>> > command line interface for use in pipes. If this were done similar to
>> > tar, we could have used any compressor we wanted, including the
>> > multithreaded versions (zstdmt)
>>
>> Well, presumably IPK creation tools can only support the matrix of
>> compression algorithms which your opkg binary can decompress. I suppose
>> someone could try to implement a plugable compression module system for
>> opkg. But given that nearly everyone uses opkg in an embedded context,
>> I'm not sure it would get much use.
>>
>> >
>> > On Tue, Sep 13, 2022 at 12:43 PM Khem Raj <raj.khem@gmail.com> wrote:
>> >
>> >     On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart
>> >     <alex.stewart@ni.com> wrote:
>> >     >
>> >     > ACK from me - apart from enabling zstd by default.
>> >     >
>> >     > On 9/13/22 07:37, Etienne Cordonnier via lists.openembedded.org
>> >     <
>> https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_bxrNjvo$
>> >
>> >     wrote:
>> >     > > This allows the use of zstd for opkg packages by using
>> >     OPKGBUILDCMD:
>> >     > > OPKGBUILDCMD = "opkg-build -Z zstd"
>> >     > >
>> >     > > Signed-off-by: Alex Feinman <afeinman@snap.com>
>> >     > > Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
>> >     > > ---
>> >     > >   meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> >     <
>> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
>> >
>> >     | 3 ++-
>> >     > >   1 file changed, 2 insertions(+), 1 deletion(-)
>> >     > >
>> >     > > diff --git a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> >     <
>> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
>> >
>> >     b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> >     <
>> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
>> >
>> >     > > index 7b351e8123..e38d9d6f3f 100644
>> >     > > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> >     <
>> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
>> >
>> >     > > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>> >     <
>> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
>> >
>> >     > > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
>> >     > >   target_localstatedir := "${localstatedir}"
>> >     > >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
>> >     > >
>> >     > > -PACKAGECONFIG ??= "libsolv"
>> >     > > +PACKAGECONFIG ??= "libsolv zstd"
>> >     >
>> >     > Building in zstd support by default is a little suspect to me.
>> >     >
>> >     > Unless I'm mistaken, OE-core will only build xz-compressed IPKs by
>> >     > default. So zstd support would be unnecessary for a distro
>> >     integrator
>> >     > who just uses upstream OE-core.
>> >     >
>> >     > For distros which use zstd compression in their packages, I think
>> it
>> >     > would be more appropriate to overwrite the opkg PACKAGECONFIG in a
>> >     > .bbappend.
>> >     >
>> >
>> >     This is perhaps fine. I do wonder if there is some performance
>> >     comparison data between xz and zstd compressed ipks
>> >     with opkg, it might help users on making this choice and also if we
>> >     should consider using
>> >     zstd by default at some point or not.
>> >
>> >     > Is there something I'm not considering here?
>> >     >
>> >     > >
>> >     > >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>> >     > >       gnupg gpgme libgpg-error,\
>> >     > > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] =
>> >     "--enable-gpg,--disable-gpg,\
>> >     > >   PACKAGECONFIG[curl] = "--enable-curl,--disable-curl,curl"
>> >     > >   PACKAGECONFIG[ssl-curl] =
>> >     "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
>> >     > >   PACKAGECONFIG[sha256] = "--enable-sha256,--disable-sha256"
>> >     > > +PACKAGECONFIG[zstd] = "--enable-zstd,--disable-zstd,zstd"
>> >     > >   PACKAGECONFIG[libsolv] =
>> >     "--with-libsolv,--without-libsolv,libsolv"
>> >     > >
>> >     > >   EXTRA_OECONF:class-native =
>> >     "--localstatedir=/${@os.path.relpath('${localstatedir}',
>> >     '${STAGING_DIR_NATIVE}')}
>> >     --sysconfdir=/${@os.path.relpath('${sysconfdir}',
>> >     '${STAGING_DIR_NATIVE}')}"
>> >     > >
>> >     > >
>> >     > >
>> >     >
>> >     > --
>> >     > Alex Stewart
>> >     > Software Engineer - NI Real-Time OS
>> >     > NI (National Instruments)
>> >     >
>> >     > alex.stewart@ni.com
>> >     >
>> >     >
>> >     > -=-=-=-=-=-=-=-=-=-=-=-
>> >     > Links: You receive all messages sent to this group.
>> >     > View/Reply Online (#170608):
>> >
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>> >     <
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_message_170608&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=_VWADuvDS3QdSEYWTnh8wNH0lOxVHty18QZynvOtpcU&e=
>> >
>> >
>> >     > Mute This Topic:
>> >
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_mt_93654146_1997914&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=QncdL2I_pCDsz7AMbsTgStzC7bt5V2x_E_gIblrtjZY&e=
>> >     <
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_mt_93654146_1997914&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=QncdL2I_pCDsz7AMbsTgStzC7bt5V2x_E_gIblrtjZY&e=
>> >
>> >
>> >     > Group Owner: openembedded-core+owner@lists.openembedded.org
>> >     <mailto:openembedded-core%2Bowner@lists.openembedded.org>
>> >     > Unsubscribe:
>> >
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_unsub&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=PxAE_3yGzbSZ21-LHz_1r3gd2_STPoZcrYDeu9vd_GM&e=
>> >     <
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_unsub&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=PxAE_3yGzbSZ21-LHz_1r3gd2_STPoZcrYDeu9vd_GM&e=
>> >
>> >      [raj.khem@gmail.com]
>> >     > -=-=-=-=-=-=-=-=-=-=-=-
>> >     >
>> >
>>
>> --
>> Alex Stewart
>> Software Engineer - NI Real-Time OS
>> NI (National Instruments)
>>
>> alex.stewart@ni.com
>>
>>
Alex Stewart Sept. 14, 2022, 3:37 p.m. UTC | #8
Thanks for checking.

I'd be interested to know if setting a higher compression level for zstd 
can get us to a similar compression ratio to xz. If so, then I think it 
could be some real value to distro maintainers to be able to *tune* 
their compression.

That's not blocking for your new PR though.


On 9/14/22 05:08, Etienne Cordonnier wrote:
> Also note that zstd's default compression level is 3 per default (from 
> a 1 to 19 scale). I did not test other compression levels.
>
> On Wed, Sep 14, 2022 at 11:58 AM Etienne Cordonnier 
> <ecordonnier@snapchat.com> wrote:
>
>     I ran a build of core-image-full-cmdline using xz and zstd, using
>     pre-populated downloads and sstate-cache directories but with
>     empty tmp directory. Here are the numbers:
>     zstd:
>     bitbake core-image-full-cmdline took 2m52.768s (real), the
>     resulting directory tmp/deploy/ipk is 1.6GB big.
>     xz:
>     bitbake core-image-full-cmdline took 4m14.214s (real), the
>     resulting directory tmp/deploy/ipk/ is 996M big
>
>     So the build with xz is 47% slower (254/172) than with zstd for
>     this "incremental build" use-case.
>
>     See the 5 biggest packages, the difference in compression-ratio
>     increases with big files:
>     build$ ls -lh tmp-zstd/deploy/ipk/core2-64/ --sort=size | head -n5
>     total 1.6G
>     -rw-r--r-- 3 ecordonnier ecordonnier  331M Sep 14 10:39
>     gcc-dbg_12.2.0-r0_core2-64.ipk
>     -rw-r--r-- 3 ecordonnier ecordonnier  264M Sep 14 10:39
>     openssl-dbg_3.0.5-r0_core2-64.ipk
>     -rw-r--r-- 3 ecordonnier ecordonnier  113M Sep 14 10:39
>     openssl-ptest_3.0.5-r0_core2-64.ipk
>     -rw-r--r-- 3 ecordonnier ecordonnier   47M Sep 14 10:39
>     binutils-dbg_2.39-r0_core2-64.ipk
>     build$ ls -lh tmp-xz/deploy/ipk/core2-64/ --sort=size | head -n5
>     total 963M
>     -rw-r--r-- 3 ecordonnier ecordonnier  214M Sep 14 10:44
>     gcc-dbg_12.2.0-r0_core2-64.ipk
>     -rw-r--r-- 3 ecordonnier ecordonnier  193M Sep 14 10:44
>     openssl-dbg_3.0.5-r0_core2-64.ipk
>     -rw-r--r-- 3 ecordonnier ecordonnier   35M Sep 14 10:44
>     openssl-ptest_3.0.5-r0_core2-64.ipk
>     -rw-r--r-- 3 ecordonnier ecordonnier   32M Sep 14 10:44
>     binutils-dbg_2.39-r0_core2-64.ipk
>     ...
>
>     I think for use-cases where the size of the ipk packages matters,
>     xz is better. For use-cases where it does not matter (ipk packages
>     not deployed), build-time matters more than compression-ratio and
>     zstd is better.
>
>     Regarding the enablement of zstd in opkg per default, I'll send a
>     new version of the patch without this line.
>     My thinking for enabling zstd per default in opkg was that zstd is
>     already enabled per default in libarchive's PACKAGECONFIG, and
>     disabling zstd in opkg's PACKAGECONFIG removes only a few lines of
>     code from opkg (opkg uses libarchive for doing the actual
>     compression/decompression).
>
>     On Tue, Sep 13, 2022 at 11:57 PM Alex Stewart
>     <alex.stewart@ni.com> wrote:
>
>
>
>         On 9/13/22 15:20, Alex Feinman wrote:
>         > I do have some numbers. When I was selling this change
>         internally, I
>         > did a comparison on our internal build.
>         >            Combined write IPK times (Σ t do_package_write_ipk)
>         > xz         162m 35s
>         > gz         52m 13s
>         > zstd       33m 49s
>         > Compression rate for zstd was closer to xz than to gz but
>         not as good
>         > as xz. For systems that have to cache packages on the device
>         with
>         > limited storage xz might be a better option, but for the
>         bulk of
>         > projects zstd is the best choice
>         > Additionally, zstd offers much faster decompression than xz
>         so the
>         > rootfs build step that includes unpacking all of the ipks,
>         takes 3m
>         > 58s with xz and 2m 44s with zstd.
>         > One other thing of note - if your build includes debug
>         packages, some
>         > may be quite large. E.g. one of our components produces a
>         2.2 GB debug
>         > package (uncompressed). On large files xz requires a
>         disproportionally
>         > large amount of time resulting in 15 minutes needed to
>         simply write
>         > ipk for the abovementioned packages, whereas zstd took about
>         45 sec.
>         > For frequent tasks like bitbaking a single package this
>         translates in
>         > a lot of saved time.
>
>         Those are certainly compelling performance improvements.
>         Assuming that
>         the final data-segment size is within 5%-ish of xz, then I
>         would agree
>         with the rest of the thread that it should probably be the
>         contemporary
>         default.
>
>         And if we make it the default compressor for OE IPKs, then
>         obviously my
>         criticism in the original PR is satisfied.
>
>         > Bottom line - I think making xz a default package compressor
>         was not
>         > entirely thought through. gzip or zstd is what the default
>         should be.
>
>         ZStandard support was only added to opkg last September [1].
>         Before
>         that, xz was the new hotness that replaced gzip. :)
>
>         [1]
>         https://urldefense.proofpoint.com/v2/url?u=https-3A__git.yoctoproject.org_opkg_commit_-3Fid-3D5dead419e94bce2e6b743ad786c1daec0e1aa294&d=DwIDaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=AhkbNonVuMIGRfPx_Qj9TsyDLWdbBqarUzFxz3aALck&m=VG_fgpCGq8Zgu73KQP1wTtb1D1TZftNpXj8jGnouPtGIBYyLIZbG8F-85POUcVN7&s=Mwoq2kkjfZhto6J5OomduJ5Rhyg_oSe-dkjeltE4Ls8&e=
>         <https://urldefense.proofpoint.com/v2/url?u=https-3A__git.yoctoproject.org_opkg_commit_-3Fid-3D5dead419e94bce2e6b743ad786c1daec0e1aa294&d=DwIDaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=AhkbNonVuMIGRfPx_Qj9TsyDLWdbBqarUzFxz3aALck&m=VG_fgpCGq8Zgu73KQP1wTtb1D1TZftNpXj8jGnouPtGIBYyLIZbG8F-85POUcVN7&s=Mwoq2kkjfZhto6J5OomduJ5Rhyg_oSe-dkjeltE4Ls8&e=>
>
>
>         > One final note: I could not find a reasonable explanation
>         for why
>         > opkg-tools require code changes to support a different
>         compressor. BSD
>         > tar and GNU tar both can easily accept compressors that they
>         have no
>         > idea about (via -I option) because all of them provide a
>         unified
>         > command line interface for use in pipes. If this were done
>         similar to
>         > tar, we could have used any compressor we wanted, including the
>         > multithreaded versions (zstdmt)
>
>         Well, presumably IPK creation tools can only support the
>         matrix of
>         compression algorithms which your opkg binary can decompress.
>         I suppose
>         someone could try to implement a plugable compression module
>         system for
>         opkg. But given that nearly everyone uses opkg in an embedded
>         context,
>         I'm not sure it would get much use.
>
>         >
>         > On Tue, Sep 13, 2022 at 12:43 PM Khem Raj
>         <raj.khem@gmail.com> wrote:
>         >
>         >     On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart
>         >     <alex.stewart@ni.com> wrote:
>         >     >
>         >     > ACK from me - apart from enabling zstd by default.
>         >     >
>         >     > On 9/13/22 07:37, Etienne Cordonnier via
>         lists.openembedded.org
>         <https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFhOF1_vg$>
>         >   
>          <https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_bxrNjvo$>
>         >     wrote:
>         >     > > This allows the use of zstd for opkg packages by using
>         >     OPKGBUILDCMD:
>         >     > > OPKGBUILDCMD = "opkg-build -Z zstd"
>         >     > >
>         >     > > Signed-off-by: Alex Feinman <afeinman@snap.com>
>         >     > > Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
>         >     > > ---
>         >     > >   meta/recipes-devtools/opkg/opkg_0.6.0.bb
>         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
>         >   
>          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>         >     | 3 ++-
>         >     > >   1 file changed, 2 insertions(+), 1 deletion(-)
>         >     > >
>         >     > > diff --git
>         a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
>         >   
>          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>         >     b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
>         >   
>          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>         >     > > index 7b351e8123..e38d9d6f3f 100644
>         >     > > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
>         >   
>          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>         >     > > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
>         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
>         >   
>          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
>         >     > > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
>         >     > >   target_localstatedir := "${localstatedir}"
>         >     > >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
>         >     > >
>         >     > > -PACKAGECONFIG ??= "libsolv"
>         >     > > +PACKAGECONFIG ??= "libsolv zstd"
>         >     >
>         >     > Building in zstd support by default is a little
>         suspect to me.
>         >     >
>         >     > Unless I'm mistaken, OE-core will only build
>         xz-compressed IPKs by
>         >     > default. So zstd support would be unnecessary for a distro
>         >     integrator
>         >     > who just uses upstream OE-core.
>         >     >
>         >     > For distros which use zstd compression in their
>         packages, I think it
>         >     > would be more appropriate to overwrite the opkg
>         PACKAGECONFIG in a
>         >     > .bbappend.
>         >     >
>         >
>         >     This is perhaps fine. I do wonder if there is some
>         performance
>         >     comparison data between xz and zstd compressed ipks
>         >     with opkg, it might help users on making this choice and
>         also if we
>         >     should consider using
>         >     zstd by default at some point or not.
>         >
>         >     > Is there something I'm not considering here?
>         >     >
>         >     > >
>         >     > >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
>         >     > >       gnupg gpgme libgpg-error,\
>         >     > > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] =
>         >     "--enable-gpg,--disable-gpg,\
>         >     > >   PACKAGECONFIG[curl] =
>         "--enable-curl,--disable-curl,curl"
>         >     > >   PACKAGECONFIG[ssl-curl] =
>         >     "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
>         >     > >   PACKAGECONFIG[sha256] =
>         "--enable-sha256,--disable-sha256"
>         >     > > +PACKAGECONFIG[zstd] =
>         "--enable-zstd,--disable-zstd,zstd"
>         >     > >   PACKAGECONFIG[libsolv] =
>         >     "--with-libsolv,--without-libsolv,libsolv"
>         >     > >
>         >     > >   EXTRA_OECONF:class-native =
>         >  "--localstatedir=/${@os.path.relpath('${localstatedir}',
>         >     '${STAGING_DIR_NATIVE}')}
>         >     --sysconfdir=/${@os.path.relpath('${sysconfdir}',
>         >     '${STAGING_DIR_NATIVE}')}"
>         >     > >
>         >     > >
>         >     > >
>         >     >
>         >     > --
>         >     > Alex Stewart
>         >     > Software Engineer - NI Real-Time OS
>         >     > NI (National Instruments)
>         >     >
>         >     > alex.stewart@ni.com
>         >     >
>         >     >
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>         >      [raj.khem@gmail.com]
>         >     > -=-=-=-=-=-=-=-=-=-=-=-
>         >     >
>         >
>
>         -- 
>         Alex Stewart
>         Software Engineer - NI Real-Time OS
>         NI (National Instruments)
>
>         alex.stewart@ni.com
>
Khem Raj Sept. 14, 2022, 3:41 p.m. UTC | #9
On Wed, Sep 14, 2022 at 8:37 AM Alex Stewart <alex.stewart@ni.com> wrote:
>
> Thanks for checking.
>
> I'd be interested to know if setting a higher compression level for zstd
> can get us to a similar compression ratio to xz. If so, then I think it
> could be some real value to distro maintainers to be able to *tune*
> their compression.

yeah it will be interesting to say try something like level 9 but I think times
might regress with that but it might be good to know the balance and perhaps
suggest size mode and performance mode of zstd instead of xz

>
> That's not blocking for your new PR though.
>
>
> On 9/14/22 05:08, Etienne Cordonnier wrote:
> > Also note that zstd's default compression level is 3 per default (from
> > a 1 to 19 scale). I did not test other compression levels.
> >
> > On Wed, Sep 14, 2022 at 11:58 AM Etienne Cordonnier
> > <ecordonnier@snapchat.com> wrote:
> >
> >     I ran a build of core-image-full-cmdline using xz and zstd, using
> >     pre-populated downloads and sstate-cache directories but with
> >     empty tmp directory. Here are the numbers:
> >     zstd:
> >     bitbake core-image-full-cmdline took 2m52.768s (real), the
> >     resulting directory tmp/deploy/ipk is 1.6GB big.
> >     xz:
> >     bitbake core-image-full-cmdline took 4m14.214s (real), the
> >     resulting directory tmp/deploy/ipk/ is 996M big
> >
> >     So the build with xz is 47% slower (254/172) than with zstd for
> >     this "incremental build" use-case.
> >
> >     See the 5 biggest packages, the difference in compression-ratio
> >     increases with big files:
> >     build$ ls -lh tmp-zstd/deploy/ipk/core2-64/ --sort=size | head -n5
> >     total 1.6G
> >     -rw-r--r-- 3 ecordonnier ecordonnier  331M Sep 14 10:39
> >     gcc-dbg_12.2.0-r0_core2-64.ipk
> >     -rw-r--r-- 3 ecordonnier ecordonnier  264M Sep 14 10:39
> >     openssl-dbg_3.0.5-r0_core2-64.ipk
> >     -rw-r--r-- 3 ecordonnier ecordonnier  113M Sep 14 10:39
> >     openssl-ptest_3.0.5-r0_core2-64.ipk
> >     -rw-r--r-- 3 ecordonnier ecordonnier   47M Sep 14 10:39
> >     binutils-dbg_2.39-r0_core2-64.ipk
> >     build$ ls -lh tmp-xz/deploy/ipk/core2-64/ --sort=size | head -n5
> >     total 963M
> >     -rw-r--r-- 3 ecordonnier ecordonnier  214M Sep 14 10:44
> >     gcc-dbg_12.2.0-r0_core2-64.ipk
> >     -rw-r--r-- 3 ecordonnier ecordonnier  193M Sep 14 10:44
> >     openssl-dbg_3.0.5-r0_core2-64.ipk
> >     -rw-r--r-- 3 ecordonnier ecordonnier   35M Sep 14 10:44
> >     openssl-ptest_3.0.5-r0_core2-64.ipk
> >     -rw-r--r-- 3 ecordonnier ecordonnier   32M Sep 14 10:44
> >     binutils-dbg_2.39-r0_core2-64.ipk
> >     ...
> >
> >     I think for use-cases where the size of the ipk packages matters,
> >     xz is better. For use-cases where it does not matter (ipk packages
> >     not deployed), build-time matters more than compression-ratio and
> >     zstd is better.
> >
> >     Regarding the enablement of zstd in opkg per default, I'll send a
> >     new version of the patch without this line.
> >     My thinking for enabling zstd per default in opkg was that zstd is
> >     already enabled per default in libarchive's PACKAGECONFIG, and
> >     disabling zstd in opkg's PACKAGECONFIG removes only a few lines of
> >     code from opkg (opkg uses libarchive for doing the actual
> >     compression/decompression).
> >
> >     On Tue, Sep 13, 2022 at 11:57 PM Alex Stewart
> >     <alex.stewart@ni.com> wrote:
> >
> >
> >
> >         On 9/13/22 15:20, Alex Feinman wrote:
> >         > I do have some numbers. When I was selling this change
> >         internally, I
> >         > did a comparison on our internal build.
> >         >            Combined write IPK times (Σ t do_package_write_ipk)
> >         > xz         162m 35s
> >         > gz         52m 13s
> >         > zstd       33m 49s
> >         > Compression rate for zstd was closer to xz than to gz but
> >         not as good
> >         > as xz. For systems that have to cache packages on the device
> >         with
> >         > limited storage xz might be a better option, but for the
> >         bulk of
> >         > projects zstd is the best choice
> >         > Additionally, zstd offers much faster decompression than xz
> >         so the
> >         > rootfs build step that includes unpacking all of the ipks,
> >         takes 3m
> >         > 58s with xz and 2m 44s with zstd.
> >         > One other thing of note - if your build includes debug
> >         packages, some
> >         > may be quite large. E.g. one of our components produces a
> >         2.2 GB debug
> >         > package (uncompressed). On large files xz requires a
> >         disproportionally
> >         > large amount of time resulting in 15 minutes needed to
> >         simply write
> >         > ipk for the abovementioned packages, whereas zstd took about
> >         45 sec.
> >         > For frequent tasks like bitbaking a single package this
> >         translates in
> >         > a lot of saved time.
> >
> >         Those are certainly compelling performance improvements.
> >         Assuming that
> >         the final data-segment size is within 5%-ish of xz, then I
> >         would agree
> >         with the rest of the thread that it should probably be the
> >         contemporary
> >         default.
> >
> >         And if we make it the default compressor for OE IPKs, then
> >         obviously my
> >         criticism in the original PR is satisfied.
> >
> >         > Bottom line - I think making xz a default package compressor
> >         was not
> >         > entirely thought through. gzip or zstd is what the default
> >         should be.
> >
> >         ZStandard support was only added to opkg last September [1].
> >         Before
> >         that, xz was the new hotness that replaced gzip. :)
> >
> >         [1]
> >         https://urldefense.proofpoint.com/v2/url?u=https-3A__git.yoctoproject.org_opkg_commit_-3Fid-3D5dead419e94bce2e6b743ad786c1daec0e1aa294&d=DwIDaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=AhkbNonVuMIGRfPx_Qj9TsyDLWdbBqarUzFxz3aALck&m=VG_fgpCGq8Zgu73KQP1wTtb1D1TZftNpXj8jGnouPtGIBYyLIZbG8F-85POUcVN7&s=Mwoq2kkjfZhto6J5OomduJ5Rhyg_oSe-dkjeltE4Ls8&e=
> >         <https://urldefense.proofpoint.com/v2/url?u=https-3A__git.yoctoproject.org_opkg_commit_-3Fid-3D5dead419e94bce2e6b743ad786c1daec0e1aa294&d=DwIDaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=AhkbNonVuMIGRfPx_Qj9TsyDLWdbBqarUzFxz3aALck&m=VG_fgpCGq8Zgu73KQP1wTtb1D1TZftNpXj8jGnouPtGIBYyLIZbG8F-85POUcVN7&s=Mwoq2kkjfZhto6J5OomduJ5Rhyg_oSe-dkjeltE4Ls8&e=>
> >
> >
> >         > One final note: I could not find a reasonable explanation
> >         for why
> >         > opkg-tools require code changes to support a different
> >         compressor. BSD
> >         > tar and GNU tar both can easily accept compressors that they
> >         have no
> >         > idea about (via -I option) because all of them provide a
> >         unified
> >         > command line interface for use in pipes. If this were done
> >         similar to
> >         > tar, we could have used any compressor we wanted, including the
> >         > multithreaded versions (zstdmt)
> >
> >         Well, presumably IPK creation tools can only support the
> >         matrix of
> >         compression algorithms which your opkg binary can decompress.
> >         I suppose
> >         someone could try to implement a plugable compression module
> >         system for
> >         opkg. But given that nearly everyone uses opkg in an embedded
> >         context,
> >         I'm not sure it would get much use.
> >
> >         >
> >         > On Tue, Sep 13, 2022 at 12:43 PM Khem Raj
> >         <raj.khem@gmail.com> wrote:
> >         >
> >         >     On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart
> >         >     <alex.stewart@ni.com> wrote:
> >         >     >
> >         >     > ACK from me - apart from enabling zstd by default.
> >         >     >
> >         >     > On 9/13/22 07:37, Etienne Cordonnier via
> >         lists.openembedded.org
> >         <https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFhOF1_vg$>
> >         >
> >          <https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_bxrNjvo$>
> >         >     wrote:
> >         >     > > This allows the use of zstd for opkg packages by using
> >         >     OPKGBUILDCMD:
> >         >     > > OPKGBUILDCMD = "opkg-build -Z zstd"
> >         >     > >
> >         >     > > Signed-off-by: Alex Feinman <afeinman@snap.com>
> >         >     > > Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>
> >         >     > > ---
> >         >     > >   meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
> >         >
> >          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
> >         >     | 3 ++-
> >         >     > >   1 file changed, 2 insertions(+), 1 deletion(-)
> >         >     > >
> >         >     > > diff --git
> >         a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
> >         >
> >          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
> >         >     b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
> >         >
> >          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
> >         >     > > index 7b351e8123..e38d9d6f3f 100644
> >         >     > > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
> >         >
> >          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
> >         >     > > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> >         <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$>
> >         >
> >          <https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$>
> >         >     > > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
> >         >     > >   target_localstatedir := "${localstatedir}"
> >         >     > >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
> >         >     > >
> >         >     > > -PACKAGECONFIG ??= "libsolv"
> >         >     > > +PACKAGECONFIG ??= "libsolv zstd"
> >         >     >
> >         >     > Building in zstd support by default is a little
> >         suspect to me.
> >         >     >
> >         >     > Unless I'm mistaken, OE-core will only build
> >         xz-compressed IPKs by
> >         >     > default. So zstd support would be unnecessary for a distro
> >         >     integrator
> >         >     > who just uses upstream OE-core.
> >         >     >
> >         >     > For distros which use zstd compression in their
> >         packages, I think it
> >         >     > would be more appropriate to overwrite the opkg
> >         PACKAGECONFIG in a
> >         >     > .bbappend.
> >         >     >
> >         >
> >         >     This is perhaps fine. I do wonder if there is some
> >         performance
> >         >     comparison data between xz and zstd compressed ipks
> >         >     with opkg, it might help users on making this choice and
> >         also if we
> >         >     should consider using
> >         >     zstd by default at some point or not.
> >         >
> >         >     > Is there something I'm not considering here?
> >         >     >
> >         >     > >
> >         >     > >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
> >         >     > >       gnupg gpgme libgpg-error,\
> >         >     > > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] =
> >         >     "--enable-gpg,--disable-gpg,\
> >         >     > >   PACKAGECONFIG[curl] =
> >         "--enable-curl,--disable-curl,curl"
> >         >     > >   PACKAGECONFIG[ssl-curl] =
> >         >     "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
> >         >     > >   PACKAGECONFIG[sha256] =
> >         "--enable-sha256,--disable-sha256"
> >         >     > > +PACKAGECONFIG[zstd] =
> >         "--enable-zstd,--disable-zstd,zstd"
> >         >     > >   PACKAGECONFIG[libsolv] =
> >         >     "--with-libsolv,--without-libsolv,libsolv"
> >         >     > >
> >         >     > >   EXTRA_OECONF:class-native =
> >         >  "--localstatedir=/${@os.path.relpath('${localstatedir}',
> >         >     '${STAGING_DIR_NATIVE}')}
> >         >     --sysconfdir=/${@os.path.relpath('${sysconfdir}',
> >         >     '${STAGING_DIR_NATIVE}')}"
> >         >     > >
> >         >     > >
> >         >     > >
> >         >     >
> >         >     > --
> >         >     > Alex Stewart
> >         >     > Software Engineer - NI Real-Time OS
> >         >     > NI (National Instruments)
> >         >     >
> >         >     > alex.stewart@ni.com
> >         >     >
> >         >     >
> >         >     > -=-=-=-=-=-=-=-=-=-=-=-
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> >         >
> >         >     > Group Owner:
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> >         >      [raj.khem@gmail.com]
> >         >     > -=-=-=-=-=-=-=-=-=-=-=-
> >         >     >
> >         >
> >
> >         --
> >         Alex Stewart
> >         Software Engineer - NI Real-Time OS
> >         NI (National Instruments)
> >
> >         alex.stewart@ni.com
> >
>
> --
> Alex Stewart
> Software Engineer - NI Real-Time OS
> NI (National Instruments)
>
> alex.stewart@ni.com
>
Etienne Cordonnier Sept. 28, 2022, 4:50 p.m. UTC | #10
I tested it a bit more today. I used the standard poky's local.conf and
added those lines. You can see that at zstd level 9 there is still a
significant difference in the compression ratio with xz for gcc-dbg which
is a big file. At zstd level 19, gcc-dbg is 241MB big instead of 214MB with
xz (12.6% more).

PACKAGE_CLASSES = "package_ipk"
ZSTD_DEFAULTS = "-T0 -19"
PACKAGECONFIG:append:pn-opkg-native = " zstd"
OPKGBUILDCMD = "opkg-build -Z zstd -a ${ZSTD_DEFAULTS}"

Zstd at level 9:

build$ ls -lh tmp-zstd-level9/deploy/ipk/core2-64/  --sort=size | head -n10
total 1.5G
-rw-r--r-- 3 ecordonnier ecordonnier  302M Sep 28 18:33
gcc-dbg_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier  249M Sep 28 18:33
openssl-dbg_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier  106M Sep 28 18:33
openssl-ptest_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   44M Sep 28 18:33
binutils-dbg_2.39-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   26M Sep 28 18:33
perl-ptest_5.36.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   23M Sep 28 18:33
gcc_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   15M Sep 28 18:32
elfutils-ptest_0.187-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   15M Sep 28 18:33
gcc-src_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   13M Sep 28 18:33
coreutils-dbg_9.1-r0_core2-64.ipk

zstd at level 19:

build$ ls -lh tmp-zstd-level19/deploy/ipk/core2-64/  --sort=size | head -n10
total 1.1G
-rw-r--r-- 3 ecordonnier ecordonnier  241M Sep 28 18:04
gcc-dbg_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier  213M Sep 28 18:03
openssl-dbg_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   36M Sep 28 17:58
binutils-dbg_2.39-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   30M Sep 28 18:00
openssl-ptest_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   22M Sep 28 17:59
perl-ptest_5.36.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   20M Sep 28 17:58
gcc_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   14M Sep 28 17:57
elfutils-ptest_0.187-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   12M Sep 28 17:58
gcc-src_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   12M Sep 28 17:57
g++_12.2.0-r0_core2-64.ipk

xz at level 9 (the default):

build$ ls -lh tmp-xz/deploy/ipk/core2-64/  --sort=size | head -n10
total 963M
-rw-r--r-- 3 ecordonnier ecordonnier  214M Sep 14 10:44
gcc-dbg_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier  193M Sep 14 10:44
openssl-dbg_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   35M Sep 14 10:44
openssl-ptest_3.0.5-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   32M Sep 14 10:44
binutils-dbg_2.39-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   20M Sep 14 10:44
perl-ptest_5.36.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   19M Sep 14 10:44
gcc_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   13M Sep 14 10:44
elfutils-ptest_0.187-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   12M Sep 14 10:44
gcc-src_12.2.0-r0_core2-64.ipk
-rw-r--r-- 3 ecordonnier ecordonnier   11M Sep 14 10:44
g++_12.2.0-r0_core2-64.ipk

On Wed, Sep 14, 2022 at 5:42 PM Khem Raj <raj.khem@gmail.com> wrote:

> On Wed, Sep 14, 2022 at 8:37 AM Alex Stewart <alex.stewart@ni.com> wrote:
> >
> > Thanks for checking.
> >
> > I'd be interested to know if setting a higher compression level for zstd
> > can get us to a similar compression ratio to xz. If so, then I think it
> > could be some real value to distro maintainers to be able to *tune*
> > their compression.
>
> yeah it will be interesting to say try something like level 9 but I think
> times
> might regress with that but it might be good to know the balance and
> perhaps
> suggest size mode and performance mode of zstd instead of xz
>
> >
> > That's not blocking for your new PR though.
> >
> >
> > On 9/14/22 05:08, Etienne Cordonnier wrote:
> > > Also note that zstd's default compression level is 3 per default (from
> > > a 1 to 19 scale). I did not test other compression levels.
> > >
> > > On Wed, Sep 14, 2022 at 11:58 AM Etienne Cordonnier
> > > <ecordonnier@snapchat.com> wrote:
> > >
> > >     I ran a build of core-image-full-cmdline using xz and zstd, using
> > >     pre-populated downloads and sstate-cache directories but with
> > >     empty tmp directory. Here are the numbers:
> > >     zstd:
> > >     bitbake core-image-full-cmdline took 2m52.768s (real), the
> > >     resulting directory tmp/deploy/ipk is 1.6GB big.
> > >     xz:
> > >     bitbake core-image-full-cmdline took 4m14.214s (real), the
> > >     resulting directory tmp/deploy/ipk/ is 996M big
> > >
> > >     So the build with xz is 47% slower (254/172) than with zstd for
> > >     this "incremental build" use-case.
> > >
> > >     See the 5 biggest packages, the difference in compression-ratio
> > >     increases with big files:
> > >     build$ ls -lh tmp-zstd/deploy/ipk/core2-64/ --sort=size | head -n5
> > >     total 1.6G
> > >     -rw-r--r-- 3 ecordonnier ecordonnier  331M Sep 14 10:39
> > >     gcc-dbg_12.2.0-r0_core2-64.ipk
> > >     -rw-r--r-- 3 ecordonnier ecordonnier  264M Sep 14 10:39
> > >     openssl-dbg_3.0.5-r0_core2-64.ipk
> > >     -rw-r--r-- 3 ecordonnier ecordonnier  113M Sep 14 10:39
> > >     openssl-ptest_3.0.5-r0_core2-64.ipk
> > >     -rw-r--r-- 3 ecordonnier ecordonnier   47M Sep 14 10:39
> > >     binutils-dbg_2.39-r0_core2-64.ipk
> > >     build$ ls -lh tmp-xz/deploy/ipk/core2-64/ --sort=size | head -n5
> > >     total 963M
> > >     -rw-r--r-- 3 ecordonnier ecordonnier  214M Sep 14 10:44
> > >     gcc-dbg_12.2.0-r0_core2-64.ipk
> > >     -rw-r--r-- 3 ecordonnier ecordonnier  193M Sep 14 10:44
> > >     openssl-dbg_3.0.5-r0_core2-64.ipk
> > >     -rw-r--r-- 3 ecordonnier ecordonnier   35M Sep 14 10:44
> > >     openssl-ptest_3.0.5-r0_core2-64.ipk
> > >     -rw-r--r-- 3 ecordonnier ecordonnier   32M Sep 14 10:44
> > >     binutils-dbg_2.39-r0_core2-64.ipk
> > >     ...
> > >
> > >     I think for use-cases where the size of the ipk packages matters,
> > >     xz is better. For use-cases where it does not matter (ipk packages
> > >     not deployed), build-time matters more than compression-ratio and
> > >     zstd is better.
> > >
> > >     Regarding the enablement of zstd in opkg per default, I'll send a
> > >     new version of the patch without this line.
> > >     My thinking for enabling zstd per default in opkg was that zstd is
> > >     already enabled per default in libarchive's PACKAGECONFIG, and
> > >     disabling zstd in opkg's PACKAGECONFIG removes only a few lines of
> > >     code from opkg (opkg uses libarchive for doing the actual
> > >     compression/decompression).
> > >
> > >     On Tue, Sep 13, 2022 at 11:57 PM Alex Stewart
> > >     <alex.stewart@ni.com> wrote:
> > >
> > >
> > >
> > >         On 9/13/22 15:20, Alex Feinman wrote:
> > >         > I do have some numbers. When I was selling this change
> > >         internally, I
> > >         > did a comparison on our internal build.
> > >         >            Combined write IPK times (Σ t
> do_package_write_ipk)
> > >         > xz         162m 35s
> > >         > gz         52m 13s
> > >         > zstd       33m 49s
> > >         > Compression rate for zstd was closer to xz than to gz but
> > >         not as good
> > >         > as xz. For systems that have to cache packages on the device
> > >         with
> > >         > limited storage xz might be a better option, but for the
> > >         bulk of
> > >         > projects zstd is the best choice
> > >         > Additionally, zstd offers much faster decompression than xz
> > >         so the
> > >         > rootfs build step that includes unpacking all of the ipks,
> > >         takes 3m
> > >         > 58s with xz and 2m 44s with zstd.
> > >         > One other thing of note - if your build includes debug
> > >         packages, some
> > >         > may be quite large. E.g. one of our components produces a
> > >         2.2 GB debug
> > >         > package (uncompressed). On large files xz requires a
> > >         disproportionally
> > >         > large amount of time resulting in 15 minutes needed to
> > >         simply write
> > >         > ipk for the abovementioned packages, whereas zstd took about
> > >         45 sec.
> > >         > For frequent tasks like bitbaking a single package this
> > >         translates in
> > >         > a lot of saved time.
> > >
> > >         Those are certainly compelling performance improvements.
> > >         Assuming that
> > >         the final data-segment size is within 5%-ish of xz, then I
> > >         would agree
> > >         with the rest of the thread that it should probably be the
> > >         contemporary
> > >         default.
> > >
> > >         And if we make it the default compressor for OE IPKs, then
> > >         obviously my
> > >         criticism in the original PR is satisfied.
> > >
> > >         > Bottom line - I think making xz a default package compressor
> > >         was not
> > >         > entirely thought through. gzip or zstd is what the default
> > >         should be.
> > >
> > >         ZStandard support was only added to opkg last September [1].
> > >         Before
> > >         that, xz was the new hotness that replaced gzip. :)
> > >
> > >         [1]
> > >
> https://urldefense.proofpoint.com/v2/url?u=https-3A__git.yoctoproject.org_opkg_commit_-3Fid-3D5dead419e94bce2e6b743ad786c1daec0e1aa294&d=DwIDaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=AhkbNonVuMIGRfPx_Qj9TsyDLWdbBqarUzFxz3aALck&m=VG_fgpCGq8Zgu73KQP1wTtb1D1TZftNpXj8jGnouPtGIBYyLIZbG8F-85POUcVN7&s=Mwoq2kkjfZhto6J5OomduJ5Rhyg_oSe-dkjeltE4Ls8&e=
> > >         <
> https://urldefense.proofpoint.com/v2/url?u=https-3A__git.yoctoproject.org_opkg_commit_-3Fid-3D5dead419e94bce2e6b743ad786c1daec0e1aa294&d=DwIDaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=AhkbNonVuMIGRfPx_Qj9TsyDLWdbBqarUzFxz3aALck&m=VG_fgpCGq8Zgu73KQP1wTtb1D1TZftNpXj8jGnouPtGIBYyLIZbG8F-85POUcVN7&s=Mwoq2kkjfZhto6J5OomduJ5Rhyg_oSe-dkjeltE4Ls8&e=
> >
> > >
> > >
> > >         > One final note: I could not find a reasonable explanation
> > >         for why
> > >         > opkg-tools require code changes to support a different
> > >         compressor. BSD
> > >         > tar and GNU tar both can easily accept compressors that they
> > >         have no
> > >         > idea about (via -I option) because all of them provide a
> > >         unified
> > >         > command line interface for use in pipes. If this were done
> > >         similar to
> > >         > tar, we could have used any compressor we wanted, including
> the
> > >         > multithreaded versions (zstdmt)
> > >
> > >         Well, presumably IPK creation tools can only support the
> > >         matrix of
> > >         compression algorithms which your opkg binary can decompress.
> > >         I suppose
> > >         someone could try to implement a plugable compression module
> > >         system for
> > >         opkg. But given that nearly everyone uses opkg in an embedded
> > >         context,
> > >         I'm not sure it would get much use.
> > >
> > >         >
> > >         > On Tue, Sep 13, 2022 at 12:43 PM Khem Raj
> > >         <raj.khem@gmail.com> wrote:
> > >         >
> > >         >     On Tue, Sep 13, 2022 at 12:19 PM Alex Stewart
> > >         >     <alex.stewart@ni.com> wrote:
> > >         >     >
> > >         >     > ACK from me - apart from enabling zstd by default.
> > >         >     >
> > >         >     > On 9/13/22 07:37, Etienne Cordonnier via
> > >         lists.openembedded.org
> > >         <
> https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFhOF1_vg$
> >
> > >         >
> > >          <
> https://urldefense.com/v3/__http://lists.openembedded.org__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_bxrNjvo$
> >
> > >         >     wrote:
> > >         >     > > This allows the use of zstd for opkg packages by
> using
> > >         >     OPKGBUILDCMD:
> > >         >     > > OPKGBUILDCMD = "opkg-build -Z zstd"
> > >         >     > >
> > >         >     > > Signed-off-by: Alex Feinman <afeinman@snap.com>
> > >         >     > > Signed-off-by: Etienne Cordonnier <
> ecordonnier@snap.com>
> > >         >     > > ---
> > >         >     > >   meta/recipes-devtools/opkg/opkg_0.6.0.bb
> > >         <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$
> >
> > >         >
> > >          <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> > >         >     | 3 ++-
> > >         >     > >   1 file changed, 2 insertions(+), 1 deletion(-)
> > >         >     > >
> > >         >     > > diff --git
> > >         a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> > >         <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$
> >
> > >         >
> > >          <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> > >         >     b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> > >         <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$
> >
> > >         >
> > >          <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> > >         >     > > index 7b351e8123..e38d9d6f3f 100644
> > >         >     > > --- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> > >         <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$
> >
> > >         >
> > >          <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> > >         >     > > +++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
> > >         <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!t0JG8eQqpsPs8clofb2phwJc6ONCKBjy-iQukKenLRVzBQvJrKTp8VsgKBI7cR8KlV3N64C3fKRHIcFFmbls2A$
> >
> > >         >
> > >          <
> https://urldefense.com/v3/__http://opkg_0.6.0.bb__;!!FbZ0ZwI3Qg!u0KgIth5yNSO1tok49C5_xo0QPHIFLa4kZBl3vVZwB-2Ui1uYBW7nt85fKXXM_VAHZ2LdFx_-65pBFo$
> >
> > >         >     > > @@ -30,7 +30,7 @@ inherit autotools pkgconfig ptest
> > >         >     > >   target_localstatedir := "${localstatedir}"
> > >         >     > >   OPKGLIBDIR ??= "${target_localstatedir}/lib"
> > >         >     > >
> > >         >     > > -PACKAGECONFIG ??= "libsolv"
> > >         >     > > +PACKAGECONFIG ??= "libsolv zstd"
> > >         >     >
> > >         >     > Building in zstd support by default is a little
> > >         suspect to me.
> > >         >     >
> > >         >     > Unless I'm mistaken, OE-core will only build
> > >         xz-compressed IPKs by
> > >         >     > default. So zstd support would be unnecessary for a
> distro
> > >         >     integrator
> > >         >     > who just uses upstream OE-core.
> > >         >     >
> > >         >     > For distros which use zstd compression in their
> > >         packages, I think it
> > >         >     > would be more appropriate to overwrite the opkg
> > >         PACKAGECONFIG in a
> > >         >     > .bbappend.
> > >         >     >
> > >         >
> > >         >     This is perhaps fine. I do wonder if there is some
> > >         performance
> > >         >     comparison data between xz and zstd compressed ipks
> > >         >     with opkg, it might help users on making this choice and
> > >         also if we
> > >         >     should consider using
> > >         >     zstd by default at some point or not.
> > >         >
> > >         >     > Is there something I'm not considering here?
> > >         >     >
> > >         >     > >
> > >         >     > >   PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
> > >         >     > >       gnupg gpgme libgpg-error,\
> > >         >     > > @@ -39,6 +39,7 @@ PACKAGECONFIG[gpg] =
> > >         >     "--enable-gpg,--disable-gpg,\
> > >         >     > >   PACKAGECONFIG[curl] =
> > >         "--enable-curl,--disable-curl,curl"
> > >         >     > >   PACKAGECONFIG[ssl-curl] =
> > >         >     "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
> > >         >     > >   PACKAGECONFIG[sha256] =
> > >         "--enable-sha256,--disable-sha256"
> > >         >     > > +PACKAGECONFIG[zstd] =
> > >         "--enable-zstd,--disable-zstd,zstd"
> > >         >     > >   PACKAGECONFIG[libsolv] =
> > >         >     "--with-libsolv,--without-libsolv,libsolv"
> > >         >     > >
> > >         >     > >   EXTRA_OECONF:class-native =
> > >         >  "--localstatedir=/${@os.path.relpath('${localstatedir}',
> > >         >     '${STAGING_DIR_NATIVE}')}
> > >         >     --sysconfdir=/${@os.path.relpath('${sysconfdir}',
> > >         >     '${STAGING_DIR_NATIVE}')}"
> > >         >     > >
> > >         >     > >
> > >         >     > >
> > >         >     >
> > >         >     > --
> > >         >     > Alex Stewart
> > >         >     > Software Engineer - NI Real-Time OS
> > >         >     > NI (National Instruments)
> > >         >     >
> > >         >     > alex.stewart@ni.com
> > >         >     >
> > >         >     >
> > >         >     > -=-=-=-=-=-=-=-=-=-=-=-
> > >         >     > Links: You receive all messages sent to this group.
> > >         >     > View/Reply Online (#170608):
> > >         >
> > >
> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_message_170608&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=_VWADuvDS3QdSEYWTnh8wNH0lOxVHty18QZynvOtpcU&e=
> > >         <
> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_message_170608&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=_VWADuvDS3QdSEYWTnh8wNH0lOxVHty18QZynvOtpcU&e=
> >
> > >         >
> > >          <
> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_message_170608&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=_VWADuvDS3QdSEYWTnh8wNH0lOxVHty18QZynvOtpcU&e=
> > >         <
> https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.openembedded.org_g_openembedded-2Dcore_message_170608&d=DwIBaQ&c=ncDTmphkJTvjIDPh0hpF_4vCHvabgGkICC2epckfdiw&r=ixV5wgZimxpcSCog35wonZKeFaeEVKUbESWNj_K-1j0&m=KvCRyrKojziBs0h9aEjEfI4R_J4FnZIK8nDBqKo_I1CpnrIJ78DBxgMrvY25Gwyh&s=_VWADuvDS3QdSEYWTnh8wNH0lOxVHty18QZynvOtpcU&e=
> >>
> > >         >
> > >         >     > Mute This Topic:
> > >         >
> > >
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> > >         Alex Stewart
> > >         Software Engineer - NI Real-Time OS
> > >         NI (National Instruments)
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> > >         alex.stewart@ni.com
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> > --
> > Alex Stewart
> > Software Engineer - NI Real-Time OS
> > NI (National Instruments)
> >
> > alex.stewart@ni.com
> >
>
Alex Stewart Sept. 28, 2022, 6:03 p.m. UTC | #11
Thanks for doing the research.

What was the build time on the zstd L19 compression vs. xz? Was there 
still an improvement?

On 9/28/22 11:50, Etienne Cordonnier wrote:
> I tested it a bit more today. I used the standard poky's local.conf 
> and added those lines. You can see that at zstd level 9 there is still 
> a significant difference in the compression ratio with xz for gcc-dbg 
> which is a big file. At zstd level 19, gcc-dbg is 241MB big instead of 
> 214MB with xz (12.6% more).
>
> PACKAGE_CLASSES = "package_ipk"
> ZSTD_DEFAULTS = "-T0 -19"
> PACKAGECONFIG:append:pn-opkg-native = " zstd"
> OPKGBUILDCMD = "opkg-build -Z zstd -a ${ZSTD_DEFAULTS}"
>
> Zstd at level 9:
>
> build$ ls -lh tmp-zstd-level9/deploy/ipk/core2-64/  --sort=size | head 
> -n10
> total 1.5G
> -rw-r--r-- 3 ecordonnier ecordonnier  302M Sep 28 18:33 
> gcc-dbg_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier  249M Sep 28 18:33 
> openssl-dbg_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier  106M Sep 28 18:33 
> openssl-ptest_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   44M Sep 28 18:33 
> binutils-dbg_2.39-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   26M Sep 28 18:33 
> perl-ptest_5.36.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   23M Sep 28 18:33 
> gcc_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   15M Sep 28 18:32 
> elfutils-ptest_0.187-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   15M Sep 28 18:33 
> gcc-src_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   13M Sep 28 18:33 
> coreutils-dbg_9.1-r0_core2-64.ipk
>
> zstd at level 19:
>
> build$ ls -lh tmp-zstd-level19/deploy/ipk/core2-64/  --sort=size | 
> head -n10
> total 1.1G
> -rw-r--r-- 3 ecordonnier ecordonnier  241M Sep 28 18:04 
> gcc-dbg_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier  213M Sep 28 18:03 
> openssl-dbg_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   36M Sep 28 17:58 
> binutils-dbg_2.39-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   30M Sep 28 18:00 
> openssl-ptest_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   22M Sep 28 17:59 
> perl-ptest_5.36.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   20M Sep 28 17:58 
> gcc_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   14M Sep 28 17:57 
> elfutils-ptest_0.187-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   12M Sep 28 17:58 
> gcc-src_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   12M Sep 28 17:57 
> g++_12.2.0-r0_core2-64.ipk
>
> xz at level 9 (the default):
>
> build$ ls -lh tmp-xz/deploy/ipk/core2-64/  --sort=size | head -n10
> total 963M
> -rw-r--r-- 3 ecordonnier ecordonnier  214M Sep 14 10:44 
> gcc-dbg_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier  193M Sep 14 10:44 
> openssl-dbg_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   35M Sep 14 10:44 
> openssl-ptest_3.0.5-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   32M Sep 14 10:44 
> binutils-dbg_2.39-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   20M Sep 14 10:44 
> perl-ptest_5.36.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   19M Sep 14 10:44 
> gcc_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   13M Sep 14 10:44 
> elfutils-ptest_0.187-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   12M Sep 14 10:44 
> gcc-src_12.2.0-r0_core2-64.ipk
> -rw-r--r-- 3 ecordonnier ecordonnier   11M Sep 14 10:44 
> g++_12.2.0-r0_core2-64.ipk
>
> On Wed, Sep 14, 2022 at 5:42 PM Khem Raj <raj.khem@gmail.com> wrote:
>
>     On Wed, Sep 14, 2022 at 8:37 AM Alex Stewart <alex.stewart@ni.com>
>     wrote:
>     >
>     > Thanks for checking.
>     >
>     > I'd be interested to know if setting a higher compression level
>     for zstd
>     > can get us to a similar compression ratio to xz. If so, then I
>     think it
>     > could be some real value to distro maintainers to be able to *tune*
>     > their compression.
>
>     yeah it will be interesting to say try something like level 9 but
>     I think times
>     might regress with that but it might be good to know the balance
>     and perhaps
>     suggest size mode and performance mode of zstd instead of xz
>
diff mbox series

Patch

diff --git a/meta/recipes-devtools/opkg/opkg_0.6.0.bb b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
index 7b351e8123..e38d9d6f3f 100644
--- a/meta/recipes-devtools/opkg/opkg_0.6.0.bb
+++ b/meta/recipes-devtools/opkg/opkg_0.6.0.bb
@@ -30,7 +30,7 @@  inherit autotools pkgconfig ptest
 target_localstatedir := "${localstatedir}"
 OPKGLIBDIR ??= "${target_localstatedir}/lib"
 
-PACKAGECONFIG ??= "libsolv"
+PACKAGECONFIG ??= "libsolv zstd"
 
 PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
     gnupg gpgme libgpg-error,\
@@ -39,6 +39,7 @@  PACKAGECONFIG[gpg] = "--enable-gpg,--disable-gpg,\
 PACKAGECONFIG[curl] = "--enable-curl,--disable-curl,curl"
 PACKAGECONFIG[ssl-curl] = "--enable-ssl-curl,--disable-ssl-curl,curl openssl"
 PACKAGECONFIG[sha256] = "--enable-sha256,--disable-sha256"
+PACKAGECONFIG[zstd] = "--enable-zstd,--disable-zstd,zstd"
 PACKAGECONFIG[libsolv] = "--with-libsolv,--without-libsolv,libsolv"
 
 EXTRA_OECONF:class-native = "--localstatedir=/${@os.path.relpath('${localstatedir}', '${STAGING_DIR_NATIVE}')} --sysconfdir=/${@os.path.relpath('${sysconfdir}', '${STAGING_DIR_NATIVE}')}"