1722574 - Tweak lazy-loading root margin defaults to 800px in all directions

Status: RESOLVED FIXED

(Core :: Layout, task)

Description

[Sean Feng [:sefeng]]

Tweak lazy-loading root margin defaults to 800px in all directions to see how it works

Comment 1

[Sean Feng [:sefeng]]

Attachment: Bug 1722574 - Tweak lazy-loading root margin defaults to 800px in all directions for EARLY_BETA_OR_EARLIER r=emilio

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b36430ed9899
Tweak lazy-loading root margin defaults to 800px in all directions for EARLY_BETA_OR_EARLIER r=emilio

Comment 3

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/b36430ed9899

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Sean: Should we enable this on all channels? Can you check the data?

Comment 5

[Sean Feng [:sefeng]]

With the tweak to 800px:

lazyload_image_not_viewport: Still a 20% regression compare 600px (8 to 10), and 30% regression compare to 300px (7 to 10). However this is better than 1000px (12).
lazyload_image_viewport_loaded: On par with 600px.
lazyload_image_viewport_loading: On par with 600px, or a slight regression.
fx_lazyload_image_page_load_ms: Seems to be a 5% to 10% regression compare to 600px for 75% percentile.

Emilio, So far we've tried 600px, 1000px and 800px. I think by far 600px is the best. Here was the analysis for it https://bugzilla.mozilla.org/show_bug.cgi?id=1713811#c0. Looks like anything over 600px isn't going to work, we could try 500px to be precise. Another option is tweaking it to 600px permanently, which would be a trade-off between resource usage and performance improvements. And it'd be hard to justify.

I think we could try 500px if we want or we could tweak it to 600px for all beta (currently only early beta) and nightly users to see how it works.

What do you think?

Comment 6

[Emilio Cobos Álvarez (:emilio)]

I think we could try 500px if we want or we could tweak it to 600px for all beta (currently only early beta) and nightly users to see how it works.

Either sounds reasonable