[telemetry] Add new measurement that counts number of GCs needed to free V8 context.

tools/perf/page_sets/page_reload_cases.py

+# Copyright 2014 The Chromium Authors. All rights reserved.

[Sami, 2015/02/17 17:14:06]

year++

[ulan, 2015/02/18 10:35:56]

Done.

+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+from telemetry.page import page as page_module
+from telemetry.page import page_set as page_set_module
+
+from page_sets import top_pages
+
+
+def _Reload(action_runner):
+  for _ in xrange(10):
+    action_runner.ReloadPage()
+    action_runner.Wait(2)

[Sami, 2015/02/17 17:14:06]

Any significance to the two seconds here? Is there any specific event we could
wait for instead?

[ulan, 2015/02/18 10:35:56]

2 seconds is just an arbitrary number. Is it possible to wait for "page-loaded"
event?

[Sami, 2015/02/18 15:30:26]

ReloadPage() already waits for the page to become interactive which is probably
good enough. If you think the sleep will help to make things less noisy, then
let's leave it in.

[ulan, 2015/02/18 15:58:41]

I see. OK, let's leave it.

+
+
+def _CreatePageClassWithReload(page_cls):
+  class DerivedSmoothPage(page_cls):  # pylint: disable=W0232
+
+    def RunPageInteractions(self, action_runner):
+      _Reload(action_runner)
+  return DerivedSmoothPage
+

[Sami, 2015/02/17 17:14:06]

nit: add an extra blank line here.

[ulan, 2015/02/18 10:35:56]

Done.

+class PageReloadCasesPageSet(page_set_module.PageSet):
+
+  """ Pages for testing GC efficiency on page reload. """
+
+  def __init__(self):
+    super(PageReloadCasesPageSet, self).__init__(
+        user_agent_type='desktop',
+        archive_data_file='data/page_reload_cases.json',

[Sami, 2015/02/17 17:14:06]

I think we can reuse the top_pages archive file here. It doesn't look like this
benchmark needs anything special from the recorded pages.

[ulan, 2015/02/18 10:35:56]

Done.

+        bucket=page_set_module.PARTNER_BUCKET)
+
+    self.AddUserStory(_CreatePageClassWithReload(
+        top_pages.GoogleWebSearchPage)(self))
+    self.AddUserStory(_CreatePageClassWithReload(
+        top_pages.GmailPage)(self))
+    self.AddUserStory(_CreatePageClassWithReload(
+        top_pages.GoogleCalendarPage)(self))
+    self.AddUserStory(_CreatePageClassWithReload(
+        top_pages.GoogleDocPage)(self))
+    self.AddUserStory(_CreatePageClassWithReload(
+        top_pages.GooglePlusPage)(self))
+    self.AddUserStory(_CreatePageClassWithReload(
+        top_pages.YoutubePage)(self))
+    self.AddUserStory(_CreatePageClassWithReload(
+        top_pages.WordpressPage)(self))
+    self.AddUserStory(_CreatePageClassWithReload(
+        top_pages.FacebookPage)(self))