From patchwork Mon Jul 18 16:17:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Quentin Schulz X-Patchwork-Id: 10349 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2DF39C433EF for ; Mon, 18 Jul 2022 16:18:03 +0000 (UTC) Received: from relay2-d.mail.gandi.net (relay2-d.mail.gandi.net [217.70.183.194]) by mx.groups.io with SMTP id smtpd.web09.29288.1658161080635870537 for ; Mon, 18 Jul 2022 09:18:01 -0700 Authentication-Results: mx.groups.io; dkim=missing; spf=none, err=permanent DNS error (domain: 0leil.net, ip: 217.70.183.194, mailfrom: foss+yocto@0leil.net) Received: (Authenticated sender: foss@0leil.net) by mail.gandi.net (Postfix) with ESMTPSA id CAF6640009; Mon, 18 Jul 2022 16:17:57 +0000 (UTC) From: Quentin Schulz To: docs@lists.yoctoproject.org Cc: Richard Purdie , Paul Eggleton , Quentin Schulz Subject: [dunfell][PATCH] ref-manual: Add XZ_THREADS and XZ_MEMLIMIT Date: Mon, 18 Jul 2022 18:17:45 +0200 Message-Id: <20220718161745.652970-1-foss+yocto@0leil.net> X-Mailer: git-send-email 2.36.1 MIME-Version: 1.0 List-Id: X-Webhook-Received: from li982-79.members.linode.com [45.33.32.79] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Mon, 18 Jul 2022 16:18:03 -0000 X-Groupsio-URL: https://lists.yoctoproject.org/g/docs/message/3062 From: Richard Purdie XZ_THREADS and XZ_MEMLIMIT were introduced in dunfell. [RP improved an original patch from Paul] Signed-off-by: Paul Eggleton Signed-off-by: Richard Purdie Signed-off-by: Quentin Schulz Reviewed-by: Michael Opdenacker --- documentation/ref-manual/ref-variables.rst | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/documentation/ref-manual/ref-variables.rst b/documentation/ref-manual/ref-variables.rst index 49e756cfb..c5facfa98 100644 --- a/documentation/ref-manual/ref-variables.rst +++ b/documentation/ref-manual/ref-variables.rst @@ -8745,4 +8745,23 @@ system and gives an overview of their function and contents. The default value of ``XSERVER``, if not specified in the machine configuration, is "xserver-xorg xf86-video-fbdev xf86-input-evdev". - + + :term:`XZ_THREADS` + Specifies the number of parallel threads that should be used when + using xz compression. + + By default this scales with core count, but is never set less than 2 + to ensure that multi-threaded mode is always used so that the output + file contents are deterministic. Builds will work with a value of 1 + but the output will differ compared to the output from the compression + generated when more than one thread is used. + + On systems where many tasks run in parallel, setting a limit to this + can be helpful in controlling system resource usage. + + :term:`XZ_MEMLIMIT` + Specifies the maximum memory the xz compression should use as a percentage + of system memory. If unconstrained the xz compressor can use large amounts of + memory and become problematic with parallelism elsewhere in the build. + "50%" has been found to be a good value. +