All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=840548

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=b5ad72e6398d4839bf3f1b2aed6561016504d7419b680aa4d94356dd98e3c67e


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

chromium-rel-mac12

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/1693b9c7c40000

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/1693b9c7c40000

[media] Log to MediaLog from VTVDA. by sandersd@chromium.org
https://chromium.googlesource.com/chromium/src/+/39e7de240b63c0103078624d09130c4a990920d2

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

Dan, is a 40% to 65% regression in GPU memory usage expected from your change? memory:chrome:all_processes:reported_by_chrome:gpu:effective_size_avg/video.html?src_crowd1080.mp4

Please ACK that you are looking into this.

Issue 840551 has been merged into this issue.

A significant regression is not expected. I will be investigating today.

 Issue 840870  has been merged into this issue.

 Issue 842833  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dfe42457393ccc5f445c6cbfd225e99e29fae6af

commit dfe42457393ccc5f445c6cbfd225e99e29fae6af
Author: Dan Sanders <sandersd@chromium.org>
Date: Tue May 15 22:04:50 2018

[media] Trace all queued images in VTVDA::OnMemoryDump().

Before this change, only output pictures were traced. This CL adds
tracing for the output (task) queue and the reorder queue. This memory
is held in IOSurfaces, and isn't attributed to Chrome in other ways.

Based on results from this new memory tracing, this CL increases the
number of requested picture buffers significantly, to avoid
pathological cases where we continue to decode pictures after running
out of picture buffers.

Bug:  840548 
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I026a8b4126a176112919f47e30c42f11e1f96b7c
Reviewed-on: https://chromium-review.googlesource.com/1053222
Commit-Queue: Dan Sanders <sandersd@chromium.org>
Reviewed-by: ccameron <ccameron@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558853}
[modify] https://crrev.com/dfe42457393ccc5f445c6cbfd225e99e29fae6af/media/gpu/BUILD.gn
[modify] https://crrev.com/dfe42457393ccc5f445c6cbfd225e99e29fae6af/media/gpu/vt_video_decode_accelerator_mac.cc
[modify] https://crrev.com/dfe42457393ccc5f445c6cbfd225e99e29fae6af/media/gpu/vt_video_decode_accelerator_mac.h

Issue 845242 has been merged into this issue.