Firefox 4 Still Has Memory Leak Problem. Switching to Chrome.

I have been a faithful user of Firefox since version 2.0. It was my favorite browser for browsing and developing on. I only used it for developing because of the firebug extension. Over the years it has gotten steadily worse as far as memory usage in each successive version.

Firefox 4 is the worst of them all in term of memory leaks. I normally have 4 to 6 tabs open continuously. After a length of time memory usage varies from 500mb to over 1gig. Memory usage will just keep going up even if you just leave your computer with the tabs open to static pages. When it gets to 1gig of memory usage my computer just slows to a crawl. I am just sick and tired of this slowness.

There is a post of Mozilla support forum here about the FF 4 memory leak problem someone experienced.

Here is a thread on Mozilla’s Facebook page about the problem.

Here is the bug on bugzilla.

Switching to Chrome

I have found a much better alternative to firefox as far as performance and memory usage. Have been using Google’s Chrome version 11 browser for past few weeks and I find it does not have a memory leak problem. I have the same number of tabs open as before and the memory usage hovers around 40mb per tab on my Mac running Snow Leopard. When a tab is closed the memory is released. Seems to run very efficiently.

Chrome also has a built in developer tool that has most of the features of firebug and some features firebug does not have. It has a audit feature that will analyze your page and give you tips on how to improve performance. Looks like they incorporated their Page Speed tool into it. Overall the browser just seems more responsive and efficient. I will just be using Firefox for testing and Chrome for all of my other browser needs.

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  1. Found your post while searching about the same issue on my Snow Leopard box. Firefox 4 was leaking memory like crazy and after a few hours of use would be up near 2GB. I disabled extensions, vacuumed the sqlite databases, etc. Nothing helped. Quitting and re-launching was the only solution and got old real fast. A bit more poking around revealed that the FF 4 binary runs in 64bit mode by default on Snow Leopard. I set the app to run in 32bit mode (Get Info in finder, tick the “Open in 32bit mode” checkbox) and all is good once again. Memory usage, with many extensions remains below 600MB.

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