All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=843625

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=63d2bf6dbe75901c900f5d963fa65c93f673a5dc0d9f501d9d872d213994d8d9


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

linux-perf

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/11605298240000

😿 Pinpoint job stopped with an error.
https://pinpoint-dot-chromeperf.appspot.com/job/11605298240000

All of the attempts failed. See the individual attempts for details on each error.

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/10715048240000

😿 Pinpoint job stopped with an error.
https://pinpoint-dot-chromeperf.appspot.com/job/10715048240000

All of the attempts failed. See the individual attempts for details on each error.

I see this error on the pinpoint job page:

Traceback (most recent call last):
  File "/base/data/home/apps/s~chromeperf/pinpoint:dev-simonhatch-81e25a04.409650844915551517/dashboard/pinpoint/models/quest/execution.py", line 98, in Poll
    self._Poll()
  File "/base/data/home/apps/s~chromeperf/pinpoint:dev-simonhatch-81e25a04.409650844915551517/dashboard/pinpoint/models/quest/run_test.py", line 210, in _Poll
    raise SwarmingTestError(self._task_id, result['exit_code'])
SwarmingTestError: The swarming task 3d88115e05cef410 failed. The test exited with code 1.

Traceback (most recent call last):
  File "../../testing/scripts/run_performance_tests.py", line 271, in <module>
    sys.exit(main())
  File "../../testing/scripts/run_performance_tests.py", line 221, in main
    benchmarks = args.benchmark_names.split(',')
AttributeError: 'Namespace' object has no attribute 'benchmark_names'

+dtu

Dave, can you try the new "apply fix" feature on this?

I'll just run on Windows.

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/14e6f074240000

📍 Found significant differences after each of 2 commits.
https://pinpoint-dot-chromeperf.appspot.com/job/14e6f074240000

Make --site-per-process the default on ToT via fieldtrial_testing_config by lukasza@chromium.org
https://chromium.googlesource.com/chromium/src/+/fb1ccf02ee8ca79e1404abfd3a3a7d540b7d2dbd

blink: Set up a cc::SoftwareImageDecodeCache for canvas image decodes. by khushalsagar@chromium.org
https://chromium.googlesource.com/chromium/src/+/49fc8a9c4a9eb46faa2258daea5bdbee48da7dcb

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

AFAICT, the pinpoint job in #c9 and #c10 as well as the charts in #c1 all report a regression in the following metric: memory:chrome:all_processes:reported_by_chrome:cc:effective_size_avg.

If this is correct, then it is expected that site-per-process (i.e. via r552589 pointed out in #c10) uses more memory - on average we expect to increase memory usage (e.g. as measured by Memory.Total.PrivateMemoryFootprint) by around 10%.