From patchwork Mon Sep 19 14:58:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Opdenacker X-Patchwork-Id: 12996 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 AFD64C54EE9 for ; Mon, 19 Sep 2022 14:58:31 +0000 (UTC) Received: from relay5-d.mail.gandi.net (relay5-d.mail.gandi.net [217.70.183.197]) by mx.groups.io with SMTP id smtpd.web10.41.1663599509771087790 for ; Mon, 19 Sep 2022 07:58:30 -0700 Authentication-Results: mx.groups.io; dkim=pass header.i=@bootlin.com header.s=gm1 header.b=po2mQk3f; spf=pass (domain: bootlin.com, ip: 217.70.183.197, mailfrom: michael.opdenacker@bootlin.com) Received: (Authenticated sender: michael.opdenacker@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id 2FE021C0002; Mon, 19 Sep 2022 14:58:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1663599507; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=y45iuFmajc7JbGljfPRyTpsknHt3+Yl8lug2lubTDh8=; b=po2mQk3fphZ06+EzOQLC26eLCSzqBvsAijs7xjsrld3fSMBEP7AIHsd/0Qmar0ngkxuNBZ RyIsKAeKUOnGxFCdoma30PnD/I34en1E5eMHD5wAe2+YBJHY2wOUQxO17Z/qpO75QNB5R6 o3YqIaSTeRSpaE3i94A1TPPlv5gjghfNpsTxLMQquM66ytjd3I7MwA8wQM6GhP/Pta/KH2 PvOapLfC4nl1sO6Zq6kyC8tIGAQvF4BqXidr+/JxpNBeaTNfCZVTyKupnspoDoA+ykrgtf 2abxAmyumqPJKvbWTkiy7qZZ+TIsZJ6MjcD99cv5X6UUda6lvkDaog8AbccURw== From: michael.opdenacker@bootlin.com To: bitbake-devel@lists.openembedded.org Cc: docs@lists.yoctoproject.org, Michael Opdenacker , Aryaman Gupta , Randy Macleod , Quentin Schulz Subject: [PATCH RESEND v3] doc: bitbake-user-manual: Add definition for BB_PRESSURE_MAX variables Date: Mon, 19 Sep 2022 16:58:12 +0200 Message-Id: <20220919145812.38756-1-michael.opdenacker@bootlin.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <17111BB47189E793.5304@lists.yoctoproject.org> References: <17111BB47189E793.5304@lists.yoctoproject.org> 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, 19 Sep 2022 14:58:31 -0000 X-Groupsio-URL: https://lists.yoctoproject.org/g/docs/message/3170 From: Michael Opdenacker From: Aryaman Gupta Add the definitions for the BB_PRESSURE_MAX{CPU|IO|MEMORY} variables in the bitbake varibales glossary. Further information on how to determine a good threshold will be added to the Yocto reference manual in a later commit. Signed-off-by: Aryaman Gupta Signed-off-by: Randy Macleod Signed-off-by: Michael Opdenacker Reviewed-by: Michael Opdenacker Reviewed-by: Quentin Schulz --- Changes in V3 (Michael Opdenacker): - Remove reference to Yocto Project manual, not documenting the variables yet. - Fix a typo ("it's" -> "its") - Simplify syntax (":" followed by "::" replaced by "::" --- .../bitbake-user-manual-ref-variables.rst | 25 +++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.rst b/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.rst index 12aef3cb..725e6c2c 100644 --- a/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.rst +++ b/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.rst @@ -483,6 +483,31 @@ overview of their function and contents. You must set this variable in the external environment in order for it to work. + :term:`BB_PRESSURE_MAX_CPU` + The threshold for maximum CPU pressure before BitBake prevents the + scheduling of new tasks. Once the :term:`BB_PRESSURE_MAX_CPU` threshold + is exceeded, new tasks are not started until the pressure subsides to + below the threshold. If :term:`BB_PRESSURE_MAX_CPU` is not set, CPU + pressure is not monitored. A threshold can be set in ``conf/local.conf`` + as:: + + BB_PRESSURE_MAX_CPU = "500" + + :term:`BB_PRESSURE_MAX_IO` + The threshold for maximum IO pressure experienced before BitBake + prevents the scheduling of new tasks. The IO pressure is regulated in the + same way as :term:`BB_PRESSURE_MAX_CPU`. At this point in time, + experiments show that IO pressure tends to be short-lived and regulating + just the CPU can help to reduce it. + + :term:`BB_PRESSURE_MAX_MEMORY` + The threshold for maximum memory pressure experienced before BitBake + prevents the scheduling of new tasks. The memory pressure is regulated in + the same way as :term:`BB_PRESSURE_MAX_CPU`. Note that any memory + pressure indicates that a system is being pushed beyond its capacity. At + this point in time, experiments show that memory pressure tends to be + short-lived and regulating just the CPU can help to reduce it. + :term:`BB_RUNFMT` Specifies the name of the executable script files (i.e. run files) saved into ``${``\ :term:`T`\ ``}``. By default, the