Project Snappy will make improvements to Firefox desktop responsiveness by completing smaller, isolated pieces of work.
This project is a responsiveness equivalent of Performance/MemShrink.
- Code that impacts the responsiveness of the Firefox desktop browser
- Out of scope
- Major architectural changes such as electrolysis (e10s) and supersnappy
- Firefox mobile, apps WebRT, B2G
- Development of performance benchmarks
- UI changes for perceived performance
- Temporary & Severe Browser Hangs
- Content Responsiveness (intermittent hangs)
- Start-up & Shutdown
- Add-on and Web page introduced slowness
- Page load
|Announcements||dev-platform and dev-planning lists||all|
|General discussion||dev-platform list||devs|
|Meetings|| Alternate Thursdays, 11am PT
|Meeting summaries||this wiki and Taras Glek's blog||all|
- May 14, 2012 - PCWorld: Firefox 13 Gets a Triple Shot of Speed Through Mozilla's 'Project Snappy'
- May 11, 2012 - WebProNews: Mozilla Makes Firefox 13 Super Speedy
- Mar 12, 2013 Benoit Girard: Shutdown Report Results
- Feb 15, 2013 Aaron Klotz: Plugin Hang UI on Aurora
- Jan 24, 2013 Vladan Djeric: Add-on performance problems
- Jan 18, 2013 Benoit Girard: Is Your Shutdown Slow? Turn On The Performance Reporter!
- Jan 11, 2013 Benoit Girard: Analyzing page load performance frame-by-frame
- Jan 4, 2013 - Taras Glek: Snappy: 2012 Summary
- Dec 5, 2012 - Benoid Girard: Analyzing Shutdown Performance
- Nov 25, 2012 - Vladan Djeric: New about:telemetry page in Firefox 19
- Sep 22, 2012 - Jared Wein: Firefox Performance/Snappy Work Week: Warsaw edition
- Sep 18, 2012 - Taras Glek: Snappy in Warsaw: pierogy-fueled hackfest
- Jun 8, 2012 - Vladan Djeric: Cache, plugin, font operations most common in chrome hang reports
- May 30, 2012 - Vladan Djeric: Profiling with the Built-in Gecko Profiler and Local Symbols on Windows
- May 17, 2012 - Vladan Djeric: Looking at my own about:telemetry data
- May 14, 2012 - Vladan Djeric: More Telemetry from Super-Slow Startups
- May 11, 2012 - Lawrence Mandel: Getting snappy – performance optimizations in Firefox 13
- Mar 21, 2012 - Vladan Djeric: Introducing Chrome Hang Reporting and the Symbolication Server
- Mar 14, 2012 - Dietrich Ayala: Firefox 11 is Smaller and Faster
- Feb 8, 2012 - Brian Bondy: Snappy optimizations for faster Firefox startup
- Jan 31, 2012 - Vladan Djeric: Telemetry from Super-slow Startups, First Impressions
Minutes and Progress Reports
Bugs tracked by the Snappy project are prioritized by adding one of [Snappy:P1], [Snappy:P2], or [Snappy:P3] to the whiteboard. Use whiteboard [Snappy] tag to nominate bugs.
- Snappy dashboard - shows recent Snappy changes
- Unprioritized Snappy bugs. These are triaged occasionally.
- Snappy:P1 bugs. These are discussed regularly in meetings.
- Snappy:P2 bugs. These are discussed occasionally in meetings. P2 is the default priority.
- Snappy:P3 bugs. These are discussed rarely in meetings.
Some other interesting bugs/lists.
- bugs that need telemetry probes implemented
- visible unresponsiveness metabug
- sync storage main-thread-io metabug
- cycle collector responsiveness metabug
- 50ms responsiveness when typing in a textbox (bug 703668)
- 60fps animations on UI operations, i.e. closing tabs (bug 702509)
- track above via telemetry
more goal thinking responsiveness goals
My (Asa) proposed core measures:
- Startup on par with IE and Chrome
- 50ms responsiveness for all non-animated primary UI interactions (list TBD)
- "Above the fold" uncached page load on par with IE and Chrome
- Back/Forward navigation as fast as Opera.
If you discover an addon that may be causing responsiveness issues
- Capture a profile of the jank with SPS Profiler.
- File a bug under Tech Evangelism/Add-ons. Describe the issue, steps to reproduce. bugzilla link.
- Upload your SPS profile + post link in bug
- Contact addon author. Authors are usually happy to make their addons more performant.
- If the developer isn't responsive we will get AMO team involved to consider delisting the offending addon version.
See bug 777397 for an example of above process.
- Firefox 16
- Firefox 15
- Start-up optimization - remove prefetch files (backed out in Firefox 16)
- No more font enumeration
- All fixed bugs
- Firefox 14
- IE profile migrator rewrite
- Async favicons
- Slow SQL Telemetry
- All fixed bugs
- Firefox 13
- Tabs on demand
- CC/GC pause reductions
- Start-up optimizations
- Front-end Telemetry
- All fixed bugs
- Firefox 12
- Inline autocomplete
- Slow SQL Telemetry
- All fixed bugs
- Firefox 11
- 712478: interactivity heuristics (to reduce jank while playing video, scrolling)
- 650968: fix personas (startup slowdown, possibly other jank)
- 729330: fix addon manager (startup slowdown)
- 699820: fix remaining main thread sqlite (significant source of jank)
- 743069: fix our tab bar responsiveness (switching tabs, tab animations, etc. We lag other browsers in this area)
- 627635 Make localstorage async (Don't allow web pages to jank us)
- 692255 get rid of windows prefetch (so we can enable library reordering for a big startup win)
- 722243 cancellable sql queries (Cancel background queries to improve interactive performance)
- 692557 Fix GFX acceleration lag (Currently GFX acceleration can result in a severe slowdown over non-accelerated case)
- 705594 Font enumeration lag (This can add minutes of lag on some windows/mac machines)
- OFTC on desktop (Needed for smooth animations)
- Necko improvements (cache, connection pools, etc)
- Information on adding new Telemetry probes
- Event Tracing: http://mxr.mozilla.org/mozilla-central/source/toolkit/xre/EventTracer.cpp#38
- Fires events at main thread event loop from background thread, measures response time
- Produces output of the form MOZ_EVENT_TRACE sample <timestamp> <duration>
- Being rolled out as part of Talos Tp5 bug 631571, will produce a responsiveness metric for "responsiveness while running Tp5"
- Peptest: bug 674606
- Responsiveness regression test harness
- Allows devs to write tests that perform various actions and tests responsiveness using EventTracer
- Project page contains everything you need to know
- Run 'make peptest' from your object directory to run the tests (see running tests for command line instructions)
- Have metrics do continuous trend analysis to see if our telemetry stats are getting better over time.
- This should use our telemetry data to tell us whether we are meeting our expectations and how far off we are
- bug 703669 tracks the implementation of this site
Placeholder section for QA and testing.
- Takeaways from 2011-12-01 Meeting
- Goal of Project:
- Big hangs (~30s) are a problem, but small hangs (~5s) may be a bigger win
- Identify where we hang, why we hang, and plug those holes
- Things on Devs Radar:
- Meta Bugs: visible responsiveness (bug 698500), sync storage (bug 699820), cycle collector (bug 698919)
- Animation hangs are most visible
- Windows, Mac, Linux are all unique -- Windows is P1 for the project
- Firefox Built-in Profiler: late Q1'2012
- Chromhang Bugs: bug 705761, bug 705287, bug 705258, bug 705594, bug 704933, bug 699051
- Small Jank: using refresh driver to measure refresh-rate performance (ie. throbber, progress bar, etc -- Asa has more ideas)
- Measuring Snappiness: Telemetry use cases
- Metrics/Automation: for trend-analysis, finding regressions with Telemetry
- Where does QA fit in?
- P1: Desktop responsiveness competitive testing
- many of these problems need stack traces (something Telemetry cannot do)
- crowd-sourcing use cases where we are less Snappy
- A-B testing with other browsers (versions of Firefox, competitor browsers)
- Ownership of Snappy P1s
- Caching issues should have patches landed in the next week or so