• APK size reduction for downloadable fonts
  • now measuring memory via test_awsy_lite
  • tsvgx and tp4m moved to Autophone

APK Size

You can see the size of every build on treeherder using Perfherder.

Here’s how the APK size changed over the quarter, for mozilla-central Android 4.0 API15+ opt builds:


The dramatic decrease in February was caused by bug 1233799, which enabled the download content service and removed fonts from the APK.

For the same period, libxul.so generally increased in size:


The recent decrease in libxul was caused by bug 1259521, an upgrade of the Android NDK.


This quarter we began tracking some memory metrics, using test_awsy_lite.


These memory measurements are generally steady over the quarter, with some small improvements.


This section tracks Perfherder graphs for mozilla-central builds of Firefox for Android, for Talos tests run on Autophone, on android-6-0-armv8-api15. The test names shown are those used on treeherder. See https://wiki.mozilla.org/Buildbot/Talos for background on Talos.

In previous quarters, these tests were running on Pandaboards; beginning this quarter, these tests run on actual phones via Autophone.


An svg-only number that measures SVG rendering performance. About half of the tests are animations or iterations of rendering. This ASAP test (tsvgx) iterates in unlimited frame-rate mode thus reflecting the maximum rendering throughput of each test. The reported value is the page load time, or, for animations/iterations – overall duration the sequence/animation took to complete. Lower values are better.


Generic page load test. Lower values are better.


No significant improvements or regressions noted for tsvgx or tp4m.


Throbber Start / Throbber Stop

These graphs are taken from http://phonedash.mozilla.org.  Browser startup performance is measured on real phones (a variety of popular devices).



There was a lot of work on Autophone this quarter, with new devices added and old devices retired or re-purposed. These graphs show devices running mozilla-central builds, of which none were in continuous use over the quarter.

Throbber Start/Stop test regressions are tracked by bug 953342; a recent regression in throbber start is under investigation in bug 1259479.


mozbench has been retired. 😦

Long live arewefastyet.com! 🙂 I’ll check in on arewefastyet.com next quarter.