Firefox/Goals/2010Q1/IO Reduction

> 50% reduction of main thread I/O

The idea of this goal is to reduce the amount of I/O calls we make on the main thread by at least 50% with the specified criteria. This criteria will likely evolve throughout the quarter as we try to better quantify our results.

With v1.1 of the criteria, this is a summary of the amount of IO operations:

• write counts: 4084
• read counts: 1073
• fsync counts: 49
• total count: 5206

Status

Work in progress. Cookie stuff should have a new patch up this week. About 27% of the IO has been removed from mozilla-central (week of March 1)!

How to help

Contact Shawn Wilsher (sdwilsh on irc, sdwilsh at mozilla dot com). I'll try to get a buglist going shortly.

Active/Landed Bugs

These bugs represent work being done to reduce IO calls. The approximate percentage of I/O calls each bug should remove from the main thread is also listed.

Bug	Owner	Status	Reads	Writes	Fsyncs	% I/O Responsible
bug 513074 - remove sync writes from current cache	Bjarne	has reviews, just needs to land		1423	3	27.3%
bug 536978 - Cookies should write asynchronously	sdwilsh	need to address review comments		1137		21.8%
bug 540765	mak	some bits landed in bug bug 522855. Revising Favicon Service interface to make it async.	10	111		2.3%
bug 513008 - Eliminate synchronous reads from cache	michal.novotny	wip patch up	75			1.4%
bug 546255 - Make nsIBrowserHistory.[un]registerOpenPage async	Unfocused		?	?		?
bug 541779 - Make site-specific zoom check asynchronous	rflint	waiting on review	?	?		?