All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=778164

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=ed7e1f976366e18d1dbbc6c4bbeeb9ba7a3d98eda838b3f1467b327eb946ce6a


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

android-nexus5

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8964771311644276528

=== Auto-CCing suspected CL author scroggo@google.com ===

Hi scroggo@google.com, 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 : Leon Scroggins III
  Commit : 8bf6a886aad1c42210fd16f372097236db34c162
  Date   : Mon Oct 23 18:04:39 2017
  Subject: Reland "Stop building SkCodec"

Bisect Details
  Configuration: android_nexus5_perf_bisect
  Benchmark    : blink_perf.image_decoder
  Metric       : decode-gif/decode-gif
  Change       : 14.04% | 412.870708333 -> 470.824208333

Revision             Result                  N
chromium@510840      412.871 +- 3.12576      6      good
chromium@510844      414.517 +- 5.31607      6      good
chromium@510846      411.975 +- 3.41525      6      good
chromium@510847      472.248 +- 5.46849      6      bad       <--
chromium@510848      472.074 +- 4.00069      6      bad
chromium@510856      471.514 +- 4.87753      6      bad
chromium@510871      472.213 +- 5.01329      6      bad
chromium@510902      470.259 +- 6.00064      6      bad
chromium@510964      470.824 +- 4.92882      6      bad

Please refer to the following doc on diagnosing blink_perf regressions:
  https://chromium.googlesource.com/chromium/src/+/master/docs/speed/benchmark_harnesses/blink_perf.md

To Run This Test
  src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests blink_perf.image_decoder

More information on addressing performance regressions:
  http://g.co/ChromePerformanceRegressions

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8964771311644276528


For feedback, file a bug with component Speed>Bisection

This is good - we originally landed the switch to SkCodec hoping to see a performance benefit. We pulled it out in the above commit due to issue 768878, which we're still investigating. So this confirms the speed-up.

That said, the image in the benchmark may not be representative of typical GIFs found on the web. Its dimensions are 2560 x 1920, which seems fairly large. This is where SkCodec really wins, though, thanks to SIMD optimizations.

We should probably add some more representative tests (including animated GIFs).

Regardless, this can be fixed once we fix issue 768878, as well as another issue that was reported in https://bugs.chromium.org/p/chromium/issues/detail?id=267883#c14. With SkCodec, the attached file (faces-1.gif) failed to decode the last several frames. When I tested the file in Skia, it worked as expected, so it's possible there's a bug in the Chromium glue.

Deleted: faces-1.gif 121 KB

	faces-1.gif 121 KB View Download

 Issue 780185  has been merged into this issue.

Thanks for all the details, scroggo! WontFix-ing per #4, but opened bug 801278 to track improvements to the benchmark.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0ffa5c7b260f5ac3290bad107d5b74faba967ceb

commit 0ffa5c7b260f5ac3290bad107d5b74faba967ceb
Author: Chris Blume <cblume@chromium.org>
Date: Wed Sep 19 22:58:02 2018

Reland SkGifCodec

SkGifCodec work was reverted as a suspected cause of a paint regression.
But it may end up being unrelated.

This is a revert of crrev.com/c/718918

Bug: 768878, 778164 , 773548 
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Ifb72574cf2012d417c223193cbd14b52ec644b9a
Reviewed-on: https://chromium-review.googlesource.com/783647
Commit-Queue: Chris Blume <cblume@chromium.org>
Reviewed-by: Leon Scroggins <scroggo@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#592590}
[modify] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/skia/BUILD.gn
[modify] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/BUILD.gn
[modify] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/gif/gif_image_decoder.cc
[modify] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/gif/gif_image_decoder.h
[modify] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/gif/gif_image_decoder_test.cc
[delete] https://crrev.com/72aa1d1634061e0de286f2dc3291d7791d7f1b40/third_party/blink/renderer/platform/image-decoders/gif/gif_image_reader.cc
[delete] https://crrev.com/72aa1d1634061e0de286f2dc3291d7791d7f1b40/third_party/blink/renderer/platform/image-decoders/gif/gif_image_reader.h
[modify] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/image_decoder.h
[modify] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/image_frame.cc
[modify] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/image_frame.h
[add] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/segment_stream.cc
[add] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/segment_stream.h
[add] https://crrev.com/0ffa5c7b260f5ac3290bad107d5b74faba967ceb/third_party/blink/renderer/platform/image-decoders/segment_stream_test.cc