836309 - Don't CC or ForgetSkippable before the first normal GC run

Status: RESOLVED DUPLICATE of bug 836457

(Core :: XPCOM, defect)

Description

[(no longer active)]

We should make sure to not gc before the first paint, if possible, since that will delay the first paint needlessly.  We may also get into a situation where the startup is taking too long, and we end up GCing making it take even longer.

Comment 1

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Generally I think we wait ten seconds before GCing at startup, which is longer than the normal period. We could increase this timer, but hopefully not many people's startup takes longer than 10 seconds. Also, the first GC is usually pretty fast.

Comment 2

[Andrew McCreight [:mccr8]]

The first CC is usually pretty huge...

Comment 3

[Andrew McCreight [:mccr8]]

Also if you are looking at this, you want to look at when the first CC is done, as if it hasn't had a GC before it, it will force one.  So if say we're not delaying the CC properly, then we end up GCing right away too.

Comment 4

[Olli Pettay [:smaug][[e-mail]]]

First CC shouldn't happen sooner than 6s after startup unless GC runs while doing some skippability
stuff, in which case it could happen as soon as 2s after GC.

Comment 5

[(no longer active)]

So, given these comments, is this bug INVALID?

Comment 6

[Andrew McCreight [:mccr8]]

Unless you've seen it happen earlier than 6s, or if that is too soon.

Though we should probably bump back the CC so its delay is longer than the GCs.  I think that's why I always get 1 CYCLE_COLLECTOR_NEED_GC right after startup.

Comment 7

[Olli Pettay [:smaug][[e-mail]]]

Perhaps we could start the CC timer only after the first GC.

Comment 8

[(no longer active)]

(In reply to comment #6)
> Unless you've seen it happen earlier than 6s, or if that is too soon.

Nah, Boris and I were just wondering about this on IRC.

> Though we should probably bump back the CC so its delay is longer than the GCs.
>  I think that's why I always get 1 CYCLE_COLLECTOR_NEED_GC right after startup.

Feel free to morph this bug for that purpose if needed.

Comment 9

[Olli Pettay [:smaug][[e-mail]]]

Um, I filed Bug 836457.