Flash plugin in Safari 64-bit in OS X 10.6 Snow Leopard causes 100% CPU

Report · Oct 05, 2009

The Flash plugin in Safari in Mac OS X 10.6.1 is causing high CPU usage of nearly 100% from the plugin alone. My Macbook Pro fans ran at almost 4000 RPM, and the CPU temperature stayed around 173 degrees F.

After I closed all Safari tabs with webpages using Flash (mostly Facebook Flash ads), the CPU usage dropped to 3% for the plugin. The fans dropped to 1800 RPM, and the CPU temperature dropped to 128 degrees F.

This does not occur in other browsers with Flash plugins in use, like Firefox, Camino, Opera, or Chrome.

This also did not occur in OS X 10.5.x.

The process name that spikes to 100% CPU is called, "Flash Player (Safari Internet plug-in)", which runs at 32-bit. The process "Safari" is running in its default 64-bit mode when this occurs.

If I visit this local Safari plugins page, (file:///Applications/Safari.app/Contents/Resources/English.lproj/Plug-ins.html)

I get, "Shockwave Flash 10.0 r32 — from file 'Flash Player.plugin'"

Is there perhaps an updated plugin I'm missing?

Report · Nov 16, 2009

This is a well-known issue with the Flash/Shockwave browser plugins and is not unique to OSX or Safari (occurs on Firefox and on Windows as well). It will cause problems even when there is no Flash on the page. It's most likely an implementation problem with Adobe. Uninstalling Flash+Shockwave player fixes the issue.

Firefox thread documenting behavior:
http://support.mozilla.com/en-US/forum/1/415618?forumId=1&comments_threshold=0&comments_parentId=415...