[Storage] Blob Storage perf tests

tools/telemetry/telemetry/web_perf/metrics/blob_timeline.py

Index: tools/telemetry/telemetry/web_perf/metrics/blob_timeline.py
diff --git a/tools/telemetry/telemetry/web_perf/metrics/blob_timeline.py b/tools/telemetry/telemetry/web_perf/metrics/blob_timeline.py
new file mode 100644
index 0000000000000000000000000000000000000000..6cdab5b6bf567ef49d3b06a2604c258848ad11da
--- /dev/null
+++ b/tools/telemetry/telemetry/web_perf/metrics/blob_timeline.py
@@ -0,0 +1,52 @@
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+from telemetry.value import list_of_scalar_values
+from telemetry.web_perf.metrics import timeline_based_metric
+
+class BlobTimelineMetric(timeline_based_metric.TimelineBasedMetric):
+  """Reports directly durations of FrameView::performLayout events.
+
+    layout: Durations of FrameView::performLayout events that were caused by and
+            start during user interaction.
+
+  Layout happens no more than once per frame, so per-frame-ness is implied.
+  """
+  WRITE_EVENT_NAME = 'Registry::RegisterBlob'
+  READ_EVENT_NAME = 'BlobRequest'
+
+  def __init__(self):
+    super(BlobTimelineMetric, self).__init__()
+
+  def AddResults(self, _model, renderer_thread, interactions, results):
+    assert interactions
+    self._AddResultsInternal(renderer_thread.parent.IterAllSlices(),
+                             interactions, results)
+
+  def _AddResultsInternal(self, events, interactions, results):
+    reads = []
+    writes = []
+    for event in events:
+      if (event.name == self.WRITE_EVENT_NAME or
+          event.name == self.READ_EVENT_NAME) and any(
+              interaction.start <= event.start <= interaction.end
+              for interaction in interactions):
+        if (event.name == self.WRITE_EVENT_NAME):
+          writes.append(event.end - event.start)
+        elif (event.name == self.READ_EVENT_NAME):
+          reads.append(event.end - event.start)
+    if reads:
+      results.AddValue(list_of_scalar_values.ListOfScalarValues(
+        page=results.current_page,
+        name='blob_reads',
+        units='ms',
+        values=reads,
+        description=('List of durations of blob part reads (not whole blob).')))
+    if writes:
+      results.AddValue(list_of_scalar_values.ListOfScalarValues(
+        page=results.current_page,
+        name='blob_writes',
+        units='ms',
+        values=writes,
+        description=('List of durations of blob writes.')))