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Issue 837025 link

Starred by 2 users

Issue metadata

Status: Assigned
Owner:
Cc:
EstimatedDays: ----
NextAction: ----
OS: Linux
Pri: 2
Type: Bug

Blocking:
issue 805098



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Increasing build time for linux official builds by ~12%

Project Member Reported by g...@chromium.org, Apr 25 2018

Issue description

Hi!

We'd like to enable AFDO for all official Linux builds of Chrome ( issue 805098 ). Compiling with AFDO turned on, in my measurements, will cost around 12% more CPU and wall time than without, and will increase clang's memory consumption by around 210MB per invocation.

dpranke@ said that this likely won't be a problem, but that we should verify with you all that it won't cause anything to break too badly. :)

If you'd like to experiment, you need two patches to enable AFDO:
- https://chromium-review.googlesource.com/c/chromium/src/+/1024637
- https://chromium-review.googlesource.com/c/chromium/src/+/1025132

(FWIW, the 210MB/TU extra memory remains dwarfed by ThinLTO's memory consumption, AFAICT.)

Thank you!
 

Comment 1 by g...@chromium.org, Apr 25 2018

Blocking: 805098
Cc: mmoss@chromium.org
Owner: eyaich@chromium.org
eyaich@, can you take a look and see if anything would be unduly impacted on your perf tests if the builds got 10-15% slower? 

mmoss@, I'm assuming official builds should be fine?
Status: Assigned (was: Untriaged)

Comment 4 by eyaich@chromium.org, Apr 26 2018

Our build times are not our limiting factor on the perf waterfall so this shouldn't be a problem.

Comment 5 by mmoss@chromium.org, Apr 26 2018

Cc: gov...@chromium.org
That would probably add about 20-30 minutes to the build. Not ideal, but that would still be about as fast as the Win Clang bots, and still faster than the Mac bots, so I guess it could be worse. +govind FYI.

Comment 6 by gov...@chromium.org, Apr 26 2018

Cc: abdulsyed@chromium.org thomasanderson@chromium.org
+ abdulsyed@ (Chrome Desktop Release TPM) & thomasanderson@ (Chrome on Linux Dev)
> That would probably add about 20-30 minutes to the build.

We should really just switch the official builds to goma.

Comment 8 by g...@chromium.org, May 10 2018

I see no objections here, so my current plan is to try to land the AFDO CL this Friday afternoon (PST) and look at the bots every now and then over the weekend.
So long as dev builds are unaffected, I'm fine with increasing the official build time.

In fact, I'd be fine with increasing the official build time much more than 12% for much less gain.

Project Member

Comment 10 by bugdroid1@chromium.org, May 15 2018

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b4a5f27eb04fc91e37c491ee8680ad0e37feb5d6

commit b4a5f27eb04fc91e37c491ee8680ad0e37feb5d6
Author: George Burgess IV <gbiv@chromium.org>
Date: Tue May 15 19:28:03 2018

[AFDO] Turn AFDO on by default for Linux official builds

This CL turns AFDO on for official builds of Linux. This appears to be a
<0.5% binary size regression, and should grant a pretty solid
performance gain.

This CL is also expected to increase build times of official builds by
around 12% (wall and CPU time). A memory usage increase of around
210-225MB per TU is also expected.

Depends on install-build-deps.sh change in r557698; it was re-run on
bots in crbug.com/841983, and devs were asked to update in "FYI: Linux
builds of Chromium need to run install-build-deps.sh after #557698".

Bug:  805098 ,  821595 , 837025
Test: See  issue 821595  for perf reports.
Change-Id: I9eafad1d20b897e77566de423f29c11cc8c13e83
Reviewed-on: https://chromium-review.googlesource.com/1025132
Commit-Queue: George Burgess <gbiv@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558806}
[modify] https://crrev.com/b4a5f27eb04fc91e37c491ee8680ad0e37feb5d6/DEPS
[modify] https://crrev.com/b4a5f27eb04fc91e37c491ee8680ad0e37feb5d6/build/config/compiler/BUILD.gn

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