This Week in Perf


  • Landed bug 514407 – should help with startups where we rebuild the search plugin cache (first start, after updates) and with UI responsiveness after managing or installing new plugins.
  • Bug 475289 has been updated, hopefully getting review this week.
  • Wrote tests for bug 507073 – looking to get it up for review over the weekend.

In other news, I’ll be landing a patch soon that adds a new ioService property to NetUtil. Once in, it will no longer be necessary to create your own reference to nsIIOService if you’re already using NetUtil for asyncCopy or newURI.

I’ll be taking some time off starting Tuesday until the 22nd, so the next update won’t be until the 25th. See you then!

This Week in Perf

Picking up from the last post, here’s what I’ve been up to for my part of the startup improvement project:


  • Landed bug 499123 – the effects on Ts as seen by Talos were mostly inconclusive (though were trending in the right direction!) and didn’t match what I had seen while testing locally.
  • Did some profiling for bugs 441355 and 496217. I posted some findings for 441355 and filed bug 512837 for a potential improvement discovered in the process. I haven’t been able to reproduce 496217 before the end of DelayedStartup() yet, though I suspect the default start page and its text field is probably what’s causing this to show up at times.

Next Steps

  • Didn’t have much time  to finish up bug 507073 due to the Firefox work week, but hope to do so next week.

This Week in Perf – Aug. 14th Edition

The Firefox team has recently started using small, well-scoped projects as a way to speed development and to better split up and coordinate tasks among many developers.  Since these projects are typically small and have well defined goals, we’re also using them train ourselves to communicate more effectively and more often (has it really been three years since I last blogged) about what our team is up to.

My project for the last couple weeks has been startup performance – mainly focusing on identifying and fixing areas where file IO is causing us pain.  Working with David, Dietrich, Drew, Vlad and Taras, we’ve found and have started working on some potential wins.

I didn’t have much time this week due to a cold and dealings with lawyers, but I started wrapping my head around the component loader in order to try having components packaged as a single JAR so that we can cut down on individual file reads during cold, non-fastload backed startups and stats in the warm case.

As far as what’s on tap for the next week I need to:

  • Write tests and finalize the patch for bug 507073.
  • Figure out the right direction for bug 507101.
  • Push to get outstanding reviews looked at. This has mostly been an issue of vacations and bandwidth and they’ll hopefully see some action within the next week.
  • File a bug with my findings for JAR’d components as I don’t really have the platform chops to properly tackle it 😉

Microsummary Manager 0.5 Alpha

Microsummary Manager 0.5 Alpha is a preview release of the next version which includes numerous new features and moves all key features to a new XPCOM component for increased performance and easier interaction with other extensions. For extension authors interested in utilizing this component, the IDL is included in this release (more details to come later once the interface is stable).
New user features/fixes:

  • Last selected generator is persisted across sessions.
  • Performance loading and displaying large numbers of generators massively improved.
  • Generators installed globally are now managed.
  • Generators in subdirectories of the profile and global generator stores are now managed.

Generator author features:

  • Authors can now include metadata to be displayed in the manager UI. Anything included in the first comment block will be parsed for data including author name, author’s website, description and instructions for use of the generator. Metadata may be formatted in either of the forms below

JavaDoc style (example):

@author John Doe
@description Extracts handy information from's front page.
@usage Bookmark any page.

The first letter may be capitalized and a colon after the attributes is optional. Each attribute should only be on one line and within the first comment node of the document.

Standard form (example):

Author: John Doe
Description: Extracts handy information from's front page.
Usage: Bookmark any page.

The first letter may be capitalized and a colon after the attributes is optional. Each attribute should only be on one line and within the first comment node of the document.