694578 - Repeatedly refreshing a page with a large webm video results in increasingly jerky playback

Status: RESOLVED WORKSFORME

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

Description

[C. Martin]

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:7.0.1) Gecko/20100101 Firefox/7.0.1
Build ID: 20110928134238

Steps to reproduce:

I'm building a multimedia project based on HTML5, center of it is a large (600 MB) webm video file. During development I have to reload quite often to get updated JavaScript files. After reloading the page with the webm video once or twice the video playback is extremely jerky or pauses for several seconds, the browser responds slowly and memory usage is extremely increased. Closing the tabs or clearing the cache does not help, I have to shut down Firefox first.


Actual results:

My guess is that Firefox doesn't free the memory/resources for the webm video upon refreshing (or closing the tab) but creates several instances. I noticed a similar bug report for SVG. I'm on Windows 7 x64. I can confirm the problem for two Windows 7 machines and a Windows XP VM. I also checked with Firefox 8, 9 and 10 (both 32 and 64 bit). Disabling hw acceleration reduced the issue but didn't resolve it completely.


Expected results:

Playback should be perfectly smooth upon refreshing, memory usage shouldn't increase. There are no similar problems when using Chrome of Opera 11.5

Comment 1

[C. Martin]

OK, sometimes you get the ideas while typing... I now tried disabling Firefox Cache completely and that resolved the issue. So the problem is related to cache managing of large (video) files?!

Comment 2

[Matthias Versen [:Matti]]

You can see the used memory in about:memory and a testcase with Steps to reproduce would be nice.

Comment 3

[Patrik]

Hi,
Currently youtube is doing a html5 trial.
http://www.youtube.com/html5
There still seems to be an issue with webm and firefox.
When I play youtube videos using html5 (webm on fireofx), then especially sound is choppy. When I turn off webm in the about:config, then everything is fine.
Patrik

Comment 4

[Ralph Giles (:rillian)]

I haven't seen a problem like this in some time. I expect it's fixed. Thanks for the report, and feel free to re-open if you still have this issue!