All About Performance

and other stuff by Taras Glek

Snappy #48: Now With Faster Shutdown

Huge Shutdown Improvement

After a couple weeks worth of telemetry data confirmed that Olli Pettay sped up shutdown by an epic >=30%: bug 818739, telemetry link.

Memory Management

Olli and Andrew McCreight continued with reducing CC pauses:

  • bug 820378: Delay CC if we’re in the middle of a GC, to allow async CC prep
  • bug 827471: Remove more wrapped JS from the CC graph
  • bug 705371: Remove pointless JSContexts from the CC graph
  • bug 785493: Reduce size of steady state cycle collector graph by about 80%
  • bug 821371: Include prep work in cycle collector pause time telemetry


Vladan landed bug 807021. Firefox should now handle DOM Local Storage writes without janking.


David Teller made search service metadata loading/migration async: bug 760036. David also made session-store loading async: bug 532150.

Aaron Klotz landed a telemetry probe to measure how often the ‘Firefox is running but not responding’ dialog is encountered on attempted startup: bug 815418. This will help us decide on whether (or when) to add functionality to kill unresponsive Firefox instances.