Firefox Startup Performance - March 5, 2010

I spent the week on-site at Mozilla HQ in Mountain View, which was great.

Talked with Bob Moss and others about expanding our startup tests to cover a variety of startup scenarios.
Spent some time tracing file IO with the top 10 extensions on AMO installed, comparing it to an empty profile (empty, with extensions) for a bug Taras filed about extension-caused file IO.
I also traced shell calls in the startup path, and found some weirdness, and yeah there are a bunch more calls with the top 10 extensions installed (empty, with extensions). Things like this should be "advertised" on extensions' pages on AMO. I'm pretty sure there's already some movement towards Talos testing extensions and posting results on AMO. I'll file a bug for getting things like this watched as well.
Taras has been making progress using Valgrind to get the function and data ordering sequence for improving code locality in our binaries.
Ryan patched and landed a change to increase the buffer size used when reading in JSON files (something the search service does during startup).