869670 - Youtube on B2G phone is slow because of nsMediaCache::FindReusableBlock

Status: RESOLVED WONTFIX

(Core :: Audio/Video: Playback, defect)

Description

[Gregor Wagner [:gwagner]]

I tried various youtube videos today and some of them are really slow (1 frame per sec).
A perf profile shows that we spend 80% the time in nsMediaCache::FindReusableBlock.

Comment 1

[cajbir (:cajbir)]

Do you have a link to a video that shows this?

Comment 2

[Gregor Wagner [:gwagner]]

(In reply to Chris Double (:doublec) from comment #1)
> Do you have a link to a video that shows this?

Sure:
https://www.youtube.com/watch?v=mOwibMyk68g

Comment 3

[cajbir (:cajbir)]

I tried this on a Nexus S running B2G and it played fine. I'll try on an Otoro when I flash it with a recent B2G.

What device are you using? Do you know what version of B2G it is? For example, I was running 'master' Gaia and 'v1-train' Gecko. 

Were you playing over Wifi or over 3G or other?

Is it possible to get an "adb logcat" result from around the time you visited the site and started the video?

Comment 4

[Gregor Wagner [:gwagner]]

This is with jld's perf build which should be b2g18 and v1-train gaia.
I am using my unagi with 256MB ram over wifi and headphones.
I also noticed that this gets better towards the end of the video.
So when I start the video it gives me a pic every 4sec or so.
After 52sec it becomes smooth and I can't see any glitches any more.

Maybe I should find another video because listening for 5 sec is already too much :)

Comment 5

[Gregor Wagner [:gwagner]]

Logcat: http://www.pastebin.mozilla.org/2383030

Replaying the video also works fine but when I restart the browser it happens again.

Comment 6

[cajbir (:cajbir)]

Thanks, logcat looks fine. I'll try on the Otoro since that has the same memory as the Unagi you are using and report back.