1614776 - Implement about:welcome static full page to measure performance gain

Status: RESOLVED FIXED

(Firefox :: Messaging System, enhancement, P1)

Description

[Punam Dahiya [:pdahiya]]

Implement about:welcome static full page to measure performance gain

Comment 1

[Punam Dahiya [:pdahiya]]

Attachment: Bug 1614776 - Implement static about:welcome full page [Do not land]

Comment 2

[Punam Dahiya [:pdahiya]]

Profile link capturing startup performance

a) using dynamic full page
MOZ_PROFILER_STARTUP=1 MOZ_PROFILER_STARTUP_ENTRIES=20000000 ./mach run --setpref trailhead.firstrun.branches=full_page_d-supercharge --temp-profile -- "about:welcome"

https://perfht.ml/39pnfM2

b) With attached patch using static fullpage welcome UI
MOZ_PROFILER_STARTUP=1 MOZ_PROFILER_STARTUP_ENTRIES=20000000 ./mach run --setpref trailhead.firstrun.staticWelcomePage=true --temp-profile -- "about:welcome"

https://perfht.ml/31LKZHs

Comment 3

[Punam Dahiya [:pdahiya]]

Attachment: Profile comparison

Comment 4

[Punam Dahiya [:pdahiya]]

Comparison of two profiles shows gain of ~500ms in startup time when switching to static about:welcome page

Comment 5

[Punam Dahiya [:pdahiya]]

Updating bug with mconley feedback over slack on above profiler recordings using capture of first few hundred milliseconds of execution

https://perfht.ml/2OPZXHg
The second row is static about:welcome. It shows a paint around the 0.54s mark - that’s the green region when about:welcome presented itself

https://perfht.ml/2HiiEPQ
green bar shows up way later in the original non-static about:welcome. It’s just over 400ms later.

Comment 6

[Punam Dahiya [:pdahiya]]

Another improvement noticed in above profile recording is around Time to First Interactive marker (TTFI) marker. TTFI for static about:welcome is 1119ms versus 2667ms for non-static about:welcome page that loads after about:newtab execution.

Comment 7

[Punam Dahiya [:pdahiya]]

Sharing Profile link capturing startup performance with latest 77 build

a) using old - without separate about:welcome
MOZ_PROFILER_STARTUP=1 MOZ_PROFILER_STARTUP_ENTRIES=20000000 ./mach run --setpref browser.aboutwelcome.enabled=false --temp-profile -- "about:welcome"

https://perfht.ml/2SwViMg

b) Using default separate about:welcome

MOZ_PROFILER_STARTUP=1 MOZ_PROFILER_STARTUP_ENTRIES=20000000 ./mach run --temp-profile -- "about:welcome"

https://perfht.ml/3fmxu7s

First meaningful paint using 'top_sites_firstrender_ts' marker for without separate about:welcome is seen at 4.9 seconds versus 3.2 seconds for separate about:welcome showing gain of ~1.7 seconds in about:welcome startup time