All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=634980

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgurTNsAoM


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

android-nexus7v2

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9005149017476224336

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9005149001442024768

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


===== SUSPECTED CL(s) =====
Subject : Reland of Shrink gn's chrome.dll - now smaller than gyp's (patchset #1 id:1 of https://codereview.chromium.org/2173453004/ )
Author  : brucedawson
Commit description:
  
Reason for revert (reland):
Problem is understood, mostly. Needed to slightly update the patch to fix it. Blink split counts were copied from gyp.

Original issue's description (with indents removed):
More work to shrink gn's chrome.dll

The three largest globals that were present in gn's chrome.dll but not in gyp's chrome.dll were eliminated by using /verbose linker output to track the object files that pulled them in and then conditionally changing source_set targets to static_library targets. Specifically:

unigram_table, in compact_enc_det.obj
- Referenced by TextResourceDecoder.obj from //third_party/WebKit/Source/core:html - some other source_set targets in this file were also modified

gpu::ApplyFramebufferAttachmentCMAAINTELResourceManager::cmaa_frag_s1_ and cmaa_frag_s2_, in gles2_cmd_apply_framebuffer_attachment_cmaa_intel.obj from //gpu/command_buffer/service:service_sources
- Referenced by gpu_command_buffer_stub.obj from //gpu/ipc/service:ipc_service_sources
- Referenced by gpu_video_decode_accelerator.obj from //media/gpu/ipc/service:service
- Referenced by gpu_child_thread.obj from //content/gpu:gpu_sources
- Referenced by gpu_video_decode_accelerator_factory.obj from //content/public/gpu:gpu_sources

As of R406709 this shrinks gn's 32-bit official chrome.dll file size from 38,907,904 bytes to 37,571,584 bytes - an unexpected 1,336,320 byte savings, mostly from the .text section. There is also ~67,000 bytes of memory-only savings in the zero-init part of the .data section.

At the same revision gyp's 32-bit official chrome.dll file size is 37,843,456 bytes - 271,872 bytes *larger* than the gn version.

There are still globals that are present in gn's chrome.dll but not gyp's chrome.dll, so the optimization technique can still be applied some more, but the priority is much lower now that gn is winning.

This is a follow-on to crrev.com/2163823002.

TBR=brettw@chromium.org,achuith@chromium.org
BUG= 624274 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2172033002
Cr-Commit-Position: refs/heads/master@{#407372}
Commit  : 6e53a2e16dc26dec41494b02da83a1221b72e7c4
Date    : Sat Jul 23 19:37:25 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev  N  Good?
chromium@407371  8842.22  69.6471  5  good
chromium@407372  9538.01  81.4383  5  bad    <--
chromium@407373  9548.74  66.4951  5  bad
chromium@407374  9485.5   45.2501  5  bad

Bisect job ran on: android_nexus7_perf_bisect
Bug ID: 634980

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests speedometer
Test Metric: jQuery-TodoMVC/jQuery-TodoMVC
Relative Change: 7.28%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus7_perf_bisect/builds/3160
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9005149017476224336


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5869342097408000

| 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!

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


===== SUSPECTED CL(s) =====
Subject : Reland of Shrink gn's chrome.dll - now smaller than gyp's (patchset #1 id:1 of https://codereview.chromium.org/2173453004/ )
Author  : brucedawson
Commit description:
  
Reason for revert (reland):
Problem is understood, mostly. Needed to slightly update the patch to fix it. Blink split counts were copied from gyp.

Original issue's description (with indents removed):
More work to shrink gn's chrome.dll

The three largest globals that were present in gn's chrome.dll but not in gyp's chrome.dll were eliminated by using /verbose linker output to track the object files that pulled them in and then conditionally changing source_set targets to static_library targets. Specifically:

unigram_table, in compact_enc_det.obj
- Referenced by TextResourceDecoder.obj from //third_party/WebKit/Source/core:html - some other source_set targets in this file were also modified

gpu::ApplyFramebufferAttachmentCMAAINTELResourceManager::cmaa_frag_s1_ and cmaa_frag_s2_, in gles2_cmd_apply_framebuffer_attachment_cmaa_intel.obj from //gpu/command_buffer/service:service_sources
- Referenced by gpu_command_buffer_stub.obj from //gpu/ipc/service:ipc_service_sources
- Referenced by gpu_video_decode_accelerator.obj from //media/gpu/ipc/service:service
- Referenced by gpu_child_thread.obj from //content/gpu:gpu_sources
- Referenced by gpu_video_decode_accelerator_factory.obj from //content/public/gpu:gpu_sources

As of R406709 this shrinks gn's 32-bit official chrome.dll file size from 38,907,904 bytes to 37,571,584 bytes - an unexpected 1,336,320 byte savings, mostly from the .text section. There is also ~67,000 bytes of memory-only savings in the zero-init part of the .data section.

At the same revision gyp's 32-bit official chrome.dll file size is 37,843,456 bytes - 271,872 bytes *larger* than the gn version.

There are still globals that are present in gn's chrome.dll but not gyp's chrome.dll, so the optimization technique can still be applied some more, but the priority is much lower now that gn is winning.

This is a follow-on to crrev.com/2163823002.

TBR=brettw@chromium.org,achuith@chromium.org
BUG= 624274 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2172033002
Cr-Commit-Position: refs/heads/master@{#407372}
Commit  : 6e53a2e16dc26dec41494b02da83a1221b72e7c4
Date    : Sat Jul 23 19:37:25 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev  N  Good?
chromium@407371  8886.47  86.6854  5  good
chromium@407372  9513.42  123.855  5  bad    <--
chromium@407373  9526.8   89.6152  5  bad
chromium@407374  9518.84  111.678  5  bad

Bisect job ran on: android_nexus7_perf_bisect
Bug ID: 634980

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests speedometer
Test Metric: jQuery-TodoMVC/jQuery-TodoMVC
Relative Change: 7.12%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus7_perf_bisect/builds/3161
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9005149001442024768


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5821550117257216

| 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!