Slow down/Crazy Memory comsumption with some sites

[thigobr]

Hi,

I noticed, starting from the build 29, a strange behavior while browsing some sites. For example, http://www.flatout.com.br/
Firefox will start to allocate and release memory in loops and the user interface becomes very unresponsive.

Some screenshots (Ubuntu x64, Firefox 30.0). Also happens on Windows.

While loading the site


After closing flatout.com.br TAB

[patrickjdempsey]

1. Does it happen only on websites that are trying to load videos as that one appears to be doing?

2. Does it happen in Firefox Safe Mode? Press Alt to get to the Menu > Help > Restart with Addons Disabled. Do not choose the Reset option.

[thigobr]

Hi patrickjdempsey,

it seems that these websites are using JavaScript. It does happen in safe mode, yes.

I've collected two profile traces that should help. Profile1.json one was collected while loading http://www.noticiasautomotivas.com.br Profile2.json while loading http://www.flatout.com.br

What seems to be taking a long time is the method Paint::PresShell::Paint.

http://wikisend.com/download/309112/profiles.zip

[rvalent3]

I also am experiencing the same issue with a few websites; not all

[Souleros]

Me too, memory use & CPU use jump way up... And it's nearly impossible for me to watch videos, especially on Netflix & Facebook!

[therube]

That ("little" Flash) ad at the top of the page (by the FlatOut! logo), is quite expensive (CPU-wise).

FlashBlock or NoScript to block the Flash, or Adblock Plus to block the ad.