*UI Jank Task Force Status Update* * * *Agenda* * * Excellent progress last week
- Spellchecking now in done in the renderer; moved a lot of disk access off I/O thread. - Launching child processes now done in background thread; off of UI / IO threads. - 30% improvement on Linux new tab creation histograms. - Memory purger now available. - First automatic purge candidate: "System memory pressure notification"? - Hibernate may not be the cause of thrashing. Investigation ongoing. - Tab switching tests now live on Windows bots. - Cookies no longer loading on startup. New investigations - Investigating using a flat file for safebrowsing instead of SQLite (need to recreate bloom filter and watch disk I/O) * * *Goal review* The team reviewed progress towards its current goals: Measure and speed up different browser UI operations: - First input event delta after tab switch + waking up after sleep - Have histogram for input event delta, but don't have it for this specific 'wake' event. - Omnibox responsiveness - No progress. - Tab switching when process is paged out - Added tab switching tests and measurements. - Whiteout duration (for the 95th percentile) --> "tab switch paint duration"? - Have histograms for whiteout, but it's a red herring. Will keep it around, but not as deterministic as onPaint roundtrip. - Startup - Added child process background thread changes. Need a perf tests for n-page session restore to prevent regressions. - Shutdown - No progress. - New tab creation - Background thread process creation...possibly a big improvement on Linux. - Tab close - May already have histograms, fast shutdown path (onUnload handlers), but didn't measure the before & after. Create a "Jank bot" that simulates a heavily overloaded system for running Jank tests. - Single core perf bots turned into 'jank bots' w/ lower memory. Also added tab switching tests (XP interactive perf.) No Disk I/O on UI, I/O threads. - Added run-time check to prevent regressions. - Moved spellchecking into renderer. - Cookie disk I/O moved out of startup. Choose whether to optimize PGO build for Renderer or Browser. - PGO build working, Carlos is investigating better optimizations. Also added many other UI Jank tweaks as well. -- Chromium Developers mailing list: chromium-dev@googlegroups.com View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev