1122570 - (mozSettings-perf) [meta] mozSettings API Performances

Status: RESOLVED WONTFIX

(Firefox OS Graveyard :: General, defect)

Description

[:gerard-majax]

People are reporting "Settings API is slow". Let's document and investigate, with this meta bug to keep an overview.

Comment 1

[Julien Wajsberg [:julienw]]

Note that I'm especially concerned about the synchronous performance of calling `mozSettings.createLock().get()`.

I don't really mind if it's slow to call asynchronous callback.

But the synchronous performance is essential because we have a lot of libraries that are simply running this code when being merely inserted and executed, and this hurts application launch performance.

Comment 2

[Gregor Wagner [:gwagner]]

(In reply to Julien Wajsberg [:julienw] from comment #1)
> Note that I'm especially concerned about the synchronous performance of
> calling `mozSettings.createLock().get()`.
> 
> I don't really mind if it's slow to call asynchronous callback.
> 
> But the synchronous performance is essential because we have a lot of
> libraries that are simply running this code when being merely inserted and
> executed, and this hurts application launch performance.

Do you have a profile where this shows up? This shouldn't be a performance bottleneck at all. We just create an object and put it into a queue. Everything happens async behind the scenes.

Comment 3

[Julien Wajsberg [:julienw]]

I don't trust our polling profiles, too much noise, too random things, we can't see anything.

See bug 1122649: I posted there a debug patch I used to find this issue. Let's move this discussion there.

Comment 4

[Bobby Chien]

[Tracking Requested - why for this release]: