New issue
Advanced search Search tips

Issue 706671 link

Starred by 1 user
Status: Fixed
Owner:
ksakamoto@chromium.org
Closed: Mar 2017
Cc:
tdres...@chromium.org
Components:
EstimatedDays: ----
NextAction: ----
OS: Linux , Android , Windows , Chrome , Mac
Pri: 2
Type: Bug



Sign in to add a comment

FCP for about:blank is logged sometimes

Project Member Reported by ksakamoto@chromium.org, Mar 30 2017 
FCP is bimodal in this benchmark (and some others):
https://chromeperf.appspot.com/report?sid=0018fa66065b6809c3309c48a7bcd469bbe0ddafa306a183f149796abbf6a4a5

Looking at one trace where timeToFirstContentfulPaint_avg is low
(https://console.developers.google.com/m/cloudstorage/b/chrome-telemetry-output/o/trace-file-id_53-2017-03-23_03-53-45-42656.html),
FCP was logged twice, 348ms for https://twitter.com/nasa and 16ms for an empty URL. The latter was for a navigation to about:blank, but was not filtered as FrameLoader trace has empty URL "", not "about:blank".

This should be a bug of trace logging.
Project Member

Comment 1 by bugdroid1@chromium.org, Mar 30 2017 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dd3783e3fbc682b2140333c56f446c1570cbe4b8

commit dd3783e3fbc682b2140333c56f446c1570cbe4b8
Author: ksakamoto <ksakamoto@chromium.org>
Date: Thu Mar 30 08:57:46 2017

Detached FrameLoader should not log snapshot trace events

FrameLoader emits object lifetime events. The destroy event is logged on
detach(), but after detach(), FrameLoader::takeObjectSnapshot() can be
called from FrameLoader::clear().

We should not log snapshot events after the destroy event, as that
confuses loading metrics (FCP, FMP, TTI).

Note for perf sheriffs: This may impact timeToFirstConentfulPaint,
timeToFirstMeaningfulPaint and timeToFirstInteractive, as this fixes a
bug of these metrics.

BUG= 706671 

Review-Url: https://codereview.chromium.org/2785873002
Cr-Commit-Position: refs/heads/master@{#460703}

[modify] https://crrev.com/dd3783e3fbc682b2140333c56f446c1570cbe4b8/third_party/WebKit/Source/core/loader/FrameLoader.cpp
[modify] https://crrev.com/dd3783e3fbc682b2140333c56f446c1570cbe4b8/third_party/WebKit/Source/core/loader/FrameLoader.h

Comment 2 by ksakamoto@chromium.org, Mar 31 2017

Status: Fixed (was: Assigned)
►

Sign in to add a comment