472676 - Flash-related CPU usage when all Flash pages are closed (Camino 2.0b1 in background using approx. 8% CPU)

Status: RESOLVED DUPLICATE of bug 474022

(Core Graveyard :: Plug-ins, defect)

Description

[buggmozz]

User-Agent:       Mozilla/5.0 (Macintosh; U; PPC Mac OS X 10.4; en; rv:1.9.0.6pre) Gecko/2008121820 Camino/2.0b1 (like Firefox/3.0.6pre)
Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X 10.4; en; rv:1.9.0.6pre) Gecko/2008121820 Camino/2.0b1 (like Firefox/3.0.6pre)

Camino 2.0b1, with Flash and Ad blocking enabled, keeps eating around 8% CPU in
the background, idling with no open windows, only if a Flash window has previously
been opened.

Reproducible: Always

Steps to Reproduce:
1.Enable Flash/Ad blocking
2.At NYTimes.com open any Flash window
3.Quit page/URL but leave browser open in dock/Check CPU usage for Camino
Actual Results:  
Activity Monitor showing close to 8% CPU usage by Camino

Comment 1

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

Can you please take a sample (as described here: http://caminobrowser.org/documentation/bugzilla/#hang) when Camino is in this condition and then attach the sample to this bug using the "Add an attachment" link above?

Comment 2

[buggmozz]

Attachment: Camino 2.0b1 Activity Monitor Sample at 8.20 % background CPU

Comment 3

[Ilya Sherman]

This might be related to bug 438575.

Can you reproduce this consistently?  Does the CPU use increase if in step 2 you open more pages/tabs?

Comment 4

[Pierre Rudloff]

Happens every time with flash games (e.g. http://www.flashportal.com/playmovie.php?id=4679 ). Doesn't seem to happen every time with little flash ads.
I tried to open 5 tabs with flash games, CPU is still around 100-120%.

Comment 5

[Pierre Rudloff]

Oups, wrong bug... Is it possible to delete ?
Sorry.

Comment 6

[buggmozz]

To Ilya Sherman,

At NYTimes.com opened then paused Flash movie: background CPU around 7 or 8%.

At NY Times.com opened Flash movie, did not pause, closed the page: background CPU around 11 or12%

At NY Times.com opened Flash movie, paused, then went to Adobe.com and opened Flash there- with no way to pause- closed page: background CPU stayed up around 15%.

I don't know about reproducing these exact percentages consistently, but yes, more or less, I can reproduce this scenario consistently. Do you see this also?

Comment 7

[Ilya Sherman]

Attachment: Corresponding WebKit sample

I can indeed reproduce this in Camino by going to http://video.nytimes.com and then closing the page.  I also see the same effect in Firefox.

Moreover, I can reproduce this in the WebKit nightly, but it takes a bit more work:
 1) Open a page with Flash content
 2) In a new window/tab, open video.nytimes.com
 3) Close video.nytimes.com
 4) Note that CPU use is elevated, but only about 1/3 of Camino's level
 5) Close the original page with Flash content
 6) Note that CPU use drops to 0

So, it seems that the bug is in Flash, but that WebKit's interaction with the Flash plug-in is more efficient than Camino/Gecko's.

Comment 8

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

Kicking this over to Core:Plug-ins for further investigation, particularly as it also affects Firefox.  

Specifically, Ilya mentioned on irc that the audio-related thread in those samples disappears in WebKit when all Flash  pages are closed, while it remains in Gecko even when all Flash pages are closed.  Josh, Michelle: any idea whose bug that is?

Comment 9

[buggmozz]

"I can indeed reproduce this in Camino by going to http://video.nytimes.com and
then closing the page.  I also see the same effect in Firefox."

Maybe I haven't understood something here, so please excuse this comment if it is showing my ignorance. 

I'm not seeing the same behavior in Firefox 3.0.5. With Firefox idling in the dock after having opened a Flash movie at http://video.nytimes.com,  I see CPU use mostly at between 0.20% and 0.60%, and never higher than 2.70%.

Comment 10

[buggmozz]

Please also note that I can only produce this background CPU eating behavior in Camino when Flash blocking is enabled. With no Flash (and Ad blocking) background CPU in Camino 2.0b1 drops to around 0.10% and 0.30%, often 0.00%, after closing page with Flash and quitting above URL.

Comment 11

[Ilya Sherman]

(In reply to comment #10)
> Please also note that I can only produce this background CPU eating behavior in
> Camino when Flash blocking is enabled. With no Flash (and Ad blocking)
> background CPU in Camino 2.0b1 drops to around 0.10% and 0.30%, often 0.00%,
> after closing page with Flash and quitting above URL.

You're right: if Flashblock is disabled, CPU use falls to 0% when closing the last Flash page.  When I tested this with Firefox, I was also using Flashblock there.  So it looks like there are two bugs here:

1) Flash continues to hold onto resources until all Flash content is closed
2) FlashBlock somehow permanently keeps Flash loaded, even when no browser windows are open

Comment 12

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

I think this bug (like bug 474153 that we spun off from it) is a probably dupe of bug 474022; see jst's bug 474022 comment 22.

Comment 14

[buggmozz]

It looks like this bug is gone. AM shows no residual background CPU usage for the 2.0b2 pre, with Flash Blocking enabled, after a Flash movie is opened, paused or stopped, and the page is then closed. It is actually showing less background CPU usage than Firefox 3.0.6.

Thanks.