Run GC after each memory test page

Run GC after each memory test page

Before this CL, no GC was run in between test, so setting --pageset-repeat > 1
lead to increased memory usage per test run, reporting inaccurate results.
This CL forces V8 GC (and attached Oilpan GC) after each test run for stable result.

More background:
Blink used to trigger V8 major GC after page unload, but this was changed to
less aggressive GC since r181187, suspected as source of this "leak".

BUG=465997
Committed: https://crrev.com/f2808ea1b048cf19cd175be3b8f986a7dd4e7559
Cr-Commit-Position: refs/heads/master@{#322318}

[kouhei (in TOK), 2015-03-23 09:26:56]

kouhei@chromium.org changed reviewers:
+ nedgnuyen@google.com, skyostil@chromium.org

[haraken, 2015-03-23 09:41:41]

haraken@chromium.org changed reviewers:
+ haraken@chromium.org

[haraken, 2015-03-23 09:41:42]

LGTM

https://codereview.chromium.org/1027133002/diff/20001/tools/perf/measurements...
File tools/perf/measurements/memory.py (right):

https://codereview.chromium.org/1027133002/diff/20001/tools/perf/measurements...
tools/perf/measurements/memory.py:26: tab.CollectGarbage()

Just to confirm, but will this trigger enough numbers of V8 & Oilpan GCs?

[kouhei (in TOK), 2015-03-23 10:21:10]

On 2015/03/23 09:41:42, haraken wrote:
> LGTM
> 
>
https://codereview.chromium.org/1027133002/diff/20001/tools/perf/measurements...
> File tools/perf/measurements/memory.py (right):
> 
>
https://codereview.chromium.org/1027133002/diff/20001/tools/perf/measurements...
> tools/perf/measurements/memory.py:26: tab.CollectGarbage()
> 
> Just to confirm, but will this trigger enough numbers of V8 & Oilpan GCs?

This will trigger 2-7 GCs:
https://code.google.com/p/chromium/codesearch#chromium/src/v8/src/heap/heap.c...

[kouhei (in TOK), 2015-03-24 01:16:49]

kouhei@chromium.org changed reviewers:
+ nednguyen@google.com
- nedgnuyen@google.com

[nednguyen, 2015-03-24 01:21:14]

https://codereview.chromium.org/1027133002/diff/20001/tools/perf/measurements...
File tools/perf/measurements/memory.py (right):

https://codereview.chromium.org/1027133002/diff/20001/tools/perf/measurements...
tools/perf/measurements/memory.py:26: tab.CollectGarbage()
What happen if the tab is already crashed here?

[kouhei (in TOK), 2015-03-24 02:25:22]

https://codereview.chromium.org/1027133002/diff/20001/tools/perf/measurements...
File tools/perf/measurements/memory.py (right):

https://codereview.chromium.org/1027133002/diff/20001/tools/perf/measurements...
tools/perf/measurements/memory.py:26: tab.CollectGarbage()
On 2015/03/24 01:21:14, nednguyen wrote:
> What happen if the tab is already crashed here?

The line throws DevtoolsTargetCrashException and it goes to next test:

  _RunUserStoryAndProcessErrorIfNeeded at
tools/telemetry/telemetry/user_story/user_story_runner.py:110
    state.DidRunUserStory(results)
  DidRunUserStory at tools/telemetry/telemetry/page/shared_page_state.py:88
    self._test.CleanUpAfterPage(self._current_page, self._current_tab)
  CleanUpAfterPage at tools/perf/measurements/memory.py:26
    tab.CollectGarbage()
  CollectGarbage at tools/telemetry/telemetry/core/tab.py:232
    self._inspector_backend.CollectGarbage()
  inner at
tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_backend.py:40
    inspector_backend._ConvertExceptionFromInspectorWebsocket(e)
  inner at
tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_backend.py:37
    return func(inspector_backend, *args, **kwargs)
  CollectGarbage at
tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_backend.py:317
    self._page.CollectGarbage()
  CollectGarbage at
tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_page.py:156
    res = self._inspector_websocket.SyncRequest(request, timeout)
  SyncRequest at
tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_websocket.py:100
    self.SendAndIgnoreResponse(req)
  SendAndIgnoreResponse at
tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_websocket.py:88
    self._socket.send(data)
  send at tools/telemetry/third_party/websocket-client/websocket.py:567
    l = self._send(data)
  _send at tools/telemetry/third_party/websocket-client/websocket.py:726
    raise e
DevtoolsTargetCrashException: Devtools target crashed

[nednguyen, 2015-03-25 17:46:30]

lgtm

[kouhei (in TOK), 2015-03-26 00:36:24]

The CQ bit was checked by kouhei@chromium.org

[commit-bot: I haz the power, 2015-03-26 00:37:48]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1027133002/20001

[commit-bot: I haz the power, 2015-03-26 04:32:19]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-26 04:32:49]

Patchset 2 (id:??) landed as
https://crrev.com/f2808ea1b048cf19cd175be3b8f986a7dd4e7559
Cr-Commit-Position: refs/heads/master@{#322318}