576457 - Flash under 3.6.6 creates high system usage/applet latency problems

Status: RESOLVED INCOMPLETE

(Core Graveyard :: Plug-ins, defect)

Description

[Michael S.]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.6) Gecko/20100628 Ubuntu/10.04 (lucid) Firefox/3.6.6
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.6) Gecko/20100628 Ubuntu/10.04 (lucid) Firefox/3.6.6

After updating to Firefox 3.6.6 (routine updates issued for Ubuntu Lucid), Flash has caused a much more significant performance hit for the system (system load/CPU Utilisation runs high, particularly for streaming media, YouTube and Vimeo and the like; RAM runs higher and further into swap) than with prior versions.  Less intensive items, iterative games (where you're not constantly mashing keys or the mouse) are still usable after the initial load, but more constant items (games and such where you ARE mashing keys, or video items) are choppy or halt, and system load quickly maxes, and nears hanging the machine unless plugin-container or firefox-bin are not killed.

Reproducible: Always

Steps to Reproduce:
1. Open a page with a Flash object (http://vimeo.com/ contains a video that replicates this problem)
2. Start playback of, in the above case, the video object.
3. Problem occurs within seconds
Actual Results:  
System load average, within 15-20 seconds, moves from (my norm) around 0.8 to 1.5 to 3.0+ within 30 seconds, CPU usage (Intel Pentium 4 Hyperthreaded) runs both percieved cores to roughly 60-80%, RAM moves to max and Swap runs to about 15% of the available 1024 GiB.

Expected Results:  
Prior to 3.6.6 update, CPU usage would hit about 50-60% across the cores, system load would level out around 1.8-2.2, RAM (depending on other threads) would sit neatly around 80% (of 488.8MiB) and swap would remain relatively unused.

No additional changes that would, as far as I know, directly affect Firefox or Flash were installed in the set of updates that were applied in the set that moved Firefox to 3.6.6; AdBlock Plus plugin remains in use, however, previously this addon helped in improving performance in these situations.  I've not let the system run to a critical point where a crash might occur, the only time anything ends up killed is if I enter a tty to kill plugin-container manually.

Comment 1

[Tyler Downer [He/Him]]

What version of flash do you have, and does this happen in safe mode? http://support.mozilla.com/en-US/kb/Safe+mode

Comment 2

[Michael S.]

(In reply to comment #1)
> What version of flash do you have, and does this happen in safe mode?
> http://support.mozilla.com/en-US/kb/Safe+mode

Sorry for the delay on response, I've been neglecting my email today.

about:plugins shows:

    File: libflashplayer.so
    Version: 
    Shockwave Flash 10.1 r53

Starting in safe mode, everything runs quite smoothly, though CPU usage is a bit higher (3-5%) than before (not unexpected, since the system is managing the plugin as a separate thread.

One thing I'll also mention, is that things did mellow down a fair bit after a new round of updates were issued (one of which was a new kernel iteration); the system load stabilizes, but everything else still increases pretty well the same, and video in particular is still quite choppy (games, on the other hand, are about on par).  I'm not the keenest mind when it comes to these things, but this tends to lead me away from Firefox's changes being the root cause.

Comment 3

[Tyler Downer [He/Him]]

If it works in safe mode, then it is probably an extension you have. Try disabling them.

Comment 4

[Benjamin Smedberg]

Resolving old bugs which are likely not relevant any more, since NPAPI plugins are deprecated.