All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=625516

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg0uq7rwkM,agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICg0ryOrAoM


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

chromium-rel-win7-x64-dual

qyearsley@, can you follow up on this?

There are ref build results and more than one builder, so I think there's a good change that this is real, but bisect hasn't confirmed it yet. Waiting for bisect results.

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

Hi oth@chromium.org, the bisect results pointed to your CL below as possibly
causing a regression. Please have a look at this info and see whether
your CL be related.


===== BISECT JOB RESULTS =====
Status: completed


===== SUSPECTED CL(s) =====
Subject : [gin] Unify snapshot loading on Windows and other platforms.
Author  : oth
Commit description:
  
Removes extra v8 snapshot and natives validation on Windows. All platforms
have the same validation henceforth.

BUG=501799

Review-Url: https://codereview.chromium.org/2103903002
Cr-Commit-Position: refs/heads/master@{#403430}
Commit  : 10b5a96b363a6ff23176d27a2e7fb1bba300f089
Date    : Fri Jul 01 09:50:11 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev  N  Good?
chromium@403429  4470.0   64.9484  5  good
chromium@403430  5667.24  107.784  5  bad    <--

Bisect job ran on: win_x64_perf_bisect
Bug ID: 625516

Test Command: src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --also-run-disabled-tests startup.cold.blank_page
Test Metric: first_main_frame_load_time/first_main_frame_load_time
Relative Change: 26.78%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/win_x64_perf_bisect/builds/1308
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9007412414561979520


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5814820499095552

| 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 Tests>AutoBisect.  Thank you!

Hi oth@, was that CL expected to have performance consequences on Windows?

It looks like it might have been unexpected that this would increase (regress) some startup metrics on Windows, can you think of a reason why that might have happened?

If it was unexpected, would it be OK to revert this at least to verify that this CL was indeed the cause of the change visible in the graphs?

The regression looks bad. Happy to revert this to see if it's to blame. I'd be surprised if so as the CL is removing code and data from the start-up path on Windows. Let's find out.

Currently stalled on unexpected bot failure with NVidia GPU when this patch is reverted:

https://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_ng/builds/254123

Not clear if this is noise or tied to the CL. The latter seems rather unlikely.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2a653192101213ec193c87e63ee119ab0dda3dd4

commit 2a653192101213ec193c87e63ee119ab0dda3dd4
Author: oth <oth@chromium.org>
Date: Wed Jul 13 10:06:14 2016

Revert of [gin] Unify snapshot loading on Windows and other platforms. (patchset #2 id:20001 of https://codereview.chromium.org/2103903002/ )

Reason for revert:
Investigate effect on Win7 startup.cold.blank_page metrics.

BUG=501799, 625516 

Original issue's description:
> [gin] Unify snapshot loading on Windows and other platforms.
>
> Removes extra v8 snapshot and natives validation on Windows. All platforms
> have the same validation henceforth.
>
> BUG=501799
>
> Committed: https://crrev.com/10b5a96b363a6ff23176d27a2e7fb1bba300f089
> Cr-Commit-Position: refs/heads/master@{#403430}

TBR=jochen@chromium.org,ben@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=501799

Review-Url: https://codereview.chromium.org/2141043002
Cr-Commit-Position: refs/heads/master@{#405111}

[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/BUILD.gn
[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/build/gn_migration.gypi
[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/BUILD.gn
[add] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/fingerprint/fingerprint_v8_snapshot.gypi
[add] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/fingerprint/fingerprint_v8_snapshot.py
[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/gin.gyp
[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/v8_initializer.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2a653192101213ec193c87e63ee119ab0dda3dd4

commit 2a653192101213ec193c87e63ee119ab0dda3dd4
Author: oth <oth@chromium.org>
Date: Wed Jul 13 10:06:14 2016

Revert of [gin] Unify snapshot loading on Windows and other platforms. (patchset #2 id:20001 of https://codereview.chromium.org/2103903002/ )

Reason for revert:
Investigate effect on Win7 startup.cold.blank_page metrics.

BUG=501799, 625516 

Original issue's description:
> [gin] Unify snapshot loading on Windows and other platforms.
>
> Removes extra v8 snapshot and natives validation on Windows. All platforms
> have the same validation henceforth.
>
> BUG=501799
>
> Committed: https://crrev.com/10b5a96b363a6ff23176d27a2e7fb1bba300f089
> Cr-Commit-Position: refs/heads/master@{#403430}

TBR=jochen@chromium.org,ben@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=501799

Review-Url: https://codereview.chromium.org/2141043002
Cr-Commit-Position: refs/heads/master@{#405111}

[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/BUILD.gn
[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/build/gn_migration.gypi
[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/BUILD.gn
[add] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/fingerprint/fingerprint_v8_snapshot.gypi
[add] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/fingerprint/fingerprint_v8_snapshot.py
[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/gin.gyp
[modify] https://crrev.com/2a653192101213ec193c87e63ee119ab0dda3dd4/gin/v8_initializer.cc

Change reverted and the perf is again better.

We'll re-examine and fix it. Thanks.