All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=699743

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgIDghOuP4AkM


Bot(s) for this bug's original alert(s):

chromium-rel-win7-gpu-ati

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8985651352860825008

=== Auto-CCing suspected CL author ccameron@chromium.org ===

Hi ccameron@chromium.org, the bisect results pointed to your CL, please take a look at the
results.


=== BISECT JOB RESULTS ===
Perf regression found with culprit

Suspected Commit
  Author : ccameron
  Commit : 7d39070d75082cd35a08775dd792d67cd2beeb40
  Date   : Sat Feb 25 00:40:36 2017
  Subject: cc: Always log shader compiler errors

Bisect Details
  Configuration: winx64ati_perf_bisect
  Benchmark    : startup.warm.blank_page
  Metric       : first_main_frame_load_time/first_main_frame_load_time
  Change       : 21.54% | 125.333333333 -> 152.333333333

Revision             Result                  N
chromium@452920      125.333 +- 7.95822      6      good
chromium@452990      126.833 +- 4.98331      6      good
chromium@453007      127.5 +- 5.78792        6      good
chromium@453016      125.333 +- 3.91578      6      good
chromium@453018      130.167 +- 8.17517      6      good
chromium@453019      150.667 +- 3.65148      6      bad       <--
chromium@453020      152.0 +- 14.2127        6      bad
chromium@453024      150.5 +- 3.39116        6      bad
chromium@453059      152.333 +- 9.76388      6      bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --pageset-repeat=2 --also-run-disabled-tests startup.warm.blank_page

Debug Info
  https://chromeperf.appspot.com/buildbucket_job_status/8985651352860825008

Is this bisect wrong?
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5224112781262848


| O O | Visit http://www.chromium.org/developers/speed-infra/perf-bug-faq
|  X  | for more information addressing perf regression bugs. For feedback,
| / \ | file a bug with component Speed>Bisection.  Thank you!

This is a significant regression in startup. Any ideas for how to not regress?

We can revert this patch -- it gave us the debug information that we needed.

Great, thanks!

Re-opening the bug, since apparently the revert didn't happen yet. (ccameron@ said he'll do the revert).

benhenry: We should probably leave bugs open until we can confirm the regression went away.

While investigating something else, I found this regression again in UMA Sampling Profiler data and filed a different bug about it with a lot of details:  crbug.com/707926 

I'll duplicate that bug into this.

 Issue 707926  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/29e1187bcf8e4c2e9b322a0f7523fc627f5ef3b4

commit 29e1187bcf8e4c2e9b322a0f7523fc627f5ef3b4
Author: ccameron <ccameron@chromium.org>
Date: Thu Apr 06 22:17:52 2017

Revert of cc: Always log shader compiler errors (patchset #2 id:20001 of https://codereview.chromium.org/2712033004/ )

Reason for revert:
Causes performance regression
BUG= 699743 

Original issue's description:
> cc: Always log shader compiler errors
>
> This is a catastrophic error, and should spam the console.
>
> BUG= 695431 
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
>
> Review-Url: https://codereview.chromium.org/2712033004
> Cr-Commit-Position: refs/heads/master@{#453019}
> Committed: https://chromium.googlesource.com/chromium/src/+/7d39070d75082cd35a08775dd792d67cd2beeb40

TBR=enne@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG= 695431 

Review-Url: https://codereview.chromium.org/2799743005
Cr-Commit-Position: refs/heads/master@{#462646}

[modify] https://crrev.com/29e1187bcf8e4c2e9b322a0f7523fc627f5ef3b4/cc/output/program_binding.cc
[modify] https://crrev.com/29e1187bcf8e4c2e9b322a0f7523fc627f5ef3b4/cc/output/program_binding.h

Confirmed that in UMA Sampling Profiler, cc::Program::InitializeInternal() goes from 400ms to 1ms after this change:

59.0.3064.0 Canary:
https://uma.googleplex.com/callstacks?sid=f8973cad2818bca805388bda61df85f0

59.0.3065.0 Canary:
https://uma.googleplex.com/callstacks?sid=6490a1b96e2c2e4fe978810c39bcdde3