From mboxrd@z Thu Jan 1 00:00:00 1970 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CDDEECCD193 for ; Mon, 20 Oct 2025 13:21:03 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vApoa-0002Bg-2m; Mon, 20 Oct 2025 09:20:44 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vApoZ-0002BX-BB for qemu-devel@nongnu.org; Mon, 20 Oct 2025 09:20:43 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vApoW-0008BJ-J7 for qemu-devel@nongnu.org; Mon, 20 Oct 2025 09:20:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1760966438; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=IpnF960+6CGuLH1X6v40Yed840a6YV3pFrj7DZy6r/U=; b=cPvizTuthCpGEDs2LFxUzbJPG11z88C5U61J178xKM/TDmPRM2b9N6dyyND5iYpieMA4nX juCTkSscoPhr2ViyOn7h0beOA9qIM0rlkOiGlim7jfAPJiSoZXWKdBlAuVgHglvQirzFBl c3bnohniI5SpVccVTfcY5gykYqfG/CI= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-407-5fex-ADhM9aOYjkOAcX2SQ-1; Mon, 20 Oct 2025 09:20:34 -0400 X-MC-Unique: 5fex-ADhM9aOYjkOAcX2SQ-1 X-Mimecast-MFC-AGG-ID: 5fex-ADhM9aOYjkOAcX2SQ_1760966433 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 0356618089A7; Mon, 20 Oct 2025 13:20:33 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.161]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E47361800577; Mon, 20 Oct 2025 13:20:30 +0000 (UTC) Date: Mon, 20 Oct 2025 14:20:27 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Thomas Huth Cc: qemu-devel@nongnu.org, Alex =?utf-8?Q?Benn=C3=A9e?= , Yonggang Luo , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Peter Maydell Subject: Re: [PATCH] gitlab-ci: Decrease the size of the compiler cache Message-ID: References: <20251020085431.23968-1-thuth@redhat.com> <22f12636-bfcf-47b6-9c61-9fd120bafdb4@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <22f12636-bfcf-47b6-9c61-9fd120bafdb4@redhat.com> User-Agent: Mutt/2.2.14 (2025-02-20) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, Oct 20, 2025 at 03:18:33PM +0200, Thomas Huth wrote: > On 20/10/2025 11.20, Daniel P. Berrangé wrote: > > On Mon, Oct 20, 2025 at 10:54:31AM +0200, Thomas Huth wrote: > > > From: Thomas Huth > > > > > > Uploading the cache from the runner takes a long time in the MSYS2 > > > job, mostly due to the size of the compiler cache. > > > However, looking at runs with a non-initialized cache, and by doing > > > a "du -sh ." in the build directory, it seems like a build only > > > takes about 236 MiB of data, so the compiler cache with 500 MiB > > > certainly contains a lot of stale files. Thus decrease the size of > > > the ccache to a more reasonable value to speed up the MSYS2 job in > > > our CI (and add a "du -sh" at the end to have a reference for the > > > required cache size in the future). > > > > > > Signed-off-by: Thomas Huth > > > --- > > > Looking at the latest runs in the CI, our recent attempt to decrease > > > the cache size by cleaning the pacman cache did not help much: > > > https://gitlab.com/qemu-project/qemu/-/jobs/11747329283 > > > ... that run contains the "pacman -Sc" command, but the "Saving cache > > > for successful job" step at the end still takes close to 20 minutes. > > > So we likely have to shrink the compiler cache, too. In this run here: > > > https://gitlab.com/thuth/qemu/-/jobs/11770708859#L1769 > > > I added a "du -sh" and you can see that the build directory only > > > takes 236 MB there. So a ccache with the size of 250M should be > > > sufficient for the MSYS2 job. > > > > FWIW, in my fork I see > > > > Cacheable calls: 638 / 647 (98.61%) > > Hits: 629 / 638 (98.59%) > > Direct: 629 / 629 (100.0%) > > Preprocessed: 0 / 629 ( 0.00%) > > Misses: 9 / 638 ( 1.41%) > > Uncacheable calls: 9 / 647 ( 1.39%) > > Local storage: > > Cache size (GB): 0.1 / 0.5 (29.54%) > > Hits: 629 / 638 (98.59%) > > Misses: 9 / 638 ( 1.41%) > > > > IOW, even ~160 MB is sufficient for 99% cache hit, so 250 MB is > > about 2/3rds spare headroom. > > Good point. So 250 MB will likely still waste time with unnecessary uploads. > > Some few MBs headroom likely still make sense in case we compile more code > in the future, so maybe we should use something like 180 MB for the cache > size? Yeah, 180 MB, and we can look at cache hit rate every now & then to see if we're exceeding it. > > I wonder if we shouldn't recursively list the msys64 cache as a debug > > aid ? > > I agree, we likely should at least temporarily add that to debug the issue. > Do you want to send a patch, or want me to do it? I'll let you. > > > .gitlab-ci.d/windows.yml | 3 ++- > > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > > > diff --git a/.gitlab-ci.d/windows.yml b/.gitlab-ci.d/windows.yml > > > index 6e1135d8b86..e2fef543899 100644 > > > --- a/.gitlab-ci.d/windows.yml > > > +++ b/.gitlab-ci.d/windows.yml > > > @@ -94,7 +94,7 @@ msys2-64bit: > > > - $env:MSYS = 'winsymlinks:native' # Enable native Windows symlink > > > - $env:CCACHE_BASEDIR = "$env:CI_PROJECT_DIR" > > > - $env:CCACHE_DIR = "$env:CCACHE_BASEDIR/ccache" > > > - - $env:CCACHE_MAXSIZE = "500M" > > > + - $env:CCACHE_MAXSIZE = "250M" > > > - $env:CCACHE_DEPEND = 1 # cache misses are too expensive with preprocessor mode > > > - $env:CC = "ccache gcc" > > > - mkdir build > > > @@ -103,5 +103,6 @@ msys2-64bit: > > > - ..\msys64\usr\bin\bash -lc "../configure $CONFIGURE_ARGS" > > > - ..\msys64\usr\bin\bash -lc "make -j$env:JOBS" > > > - ..\msys64\usr\bin\bash -lc "make check MTESTARGS='$TEST_ARGS' || { cat meson-logs/testlog.txt; exit 1; } ;" > > > + - ..\msys64\usr\bin\bash -lc "du -sh ." > > > > Do we want to keep this in the final commit ? > > > We have ccache size printed, and we could do with msys64/var/cache > > size being printed at least. > > Well, the cache can collect stale garbage, as you can currently see in the > CI jobs of the qemu-project, but the build folder should give you a very > clear picture of how many MiBs of object code are really necessary, so I'd > prefer to keep it (at least for a while). Ok With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|