999671 - GC taking too long on my beautiful earth

Status: RESOLVED WORKSFORME

(Core :: JavaScript: GC, defect)

Description

[(no longer active)]

https://mybeautifulearth.withgoogle.com/

See the profile link.  We spend around 25% of our time GCing during scrolling.

Comment 1

[Terrence Cole [:terrence]]

Thankfully, it's not a regression from our new generational GC: we're only spending 0.8% of our GC time in Nursery::collect, according to the trace above.

59.1% in processMarkStackTop is normal marking. 16% nested in this is JSFunction::trace, so we can assume there a bunch of functions in play: not surprising. Really there's nothing that sticks out here, so the next question is why we're GCing so much here. Running this locally on my 500+ tab profile, I'm not actually getting much of any GC activity on this page at all. Retrying in a fresh profile, I'm seeing lots more GCs, but they are entirely due to CC_WAITING. Our max-pause is a quite reasonable 30-50ms, but I am seeing severe jankyness -- maybe my slow linux graphics drivers?

Comment 2

[(no longer active)]

FWIW I tested this on Mac, on my normal daily profile (with <100 tabs!).  I also have AdBlock Plus installed in this profile, and there are js frames elsewhere in the profile coming from that, so it might be playing a role here too.

Comment 3

[Jon Coppeard (:jonco) (PTO until Monday 30th)]

Site no longer exists and bug does not reproduce with https://web.archive.org/web/20140620024941/https://mybeautifulearth.withgoogle.com/