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Reducing Firefox's Memory Use

Posted by Zonk on from the that-would-be-really-nice dept.

An anonymous reader writes "Many people have complained about Firefox's memory use. Federico Mena-Quintero has a proposal for reducing the amount of memory used to store images, which, in his proof of concept code, 'reduced the cumulative memory usage... by a factor of 5.5.'."

2 of 110 comments (clear)

  1. Easier solution by plover · · Score: 4, Insightful
    Buy more memory. It seems to be the rest of the industry's answer to resource hogging software. Look at all the bloatware out there: XML, JVMs, .NET, etc. The rest of the world is building for 1GB boxes, so who cares how efficient their code is anymore?

    Coming from me, this is sarcasm, but it's a depressingly prevalent real attitude in the industry.

    --
    John
  2. Don't try to play Operating System by Clueless+Moron · · Score: 4, Insightful
    While it looks like a nifty idea at first glance, this kind of memory optimization is ultimately pointless when you have a nifty demand-paged vmem kernel like Linux.

    Consider: since my box has 1G of memory, I do want the X server to hang on the all those pixmaps, because that makes firefax run fast. The hack would make it waste CPU time re-uncompressing images, whether it's needed or not.

    With the way Firefox works now, if memory does start to run short, well, that's when the kernel will start paging things out based on its clever working set algorithms. If a given pixmap area in the X server hasn't been accessed in quite a while, it'll get swapped out to disk and the memory reclaimed. If the pixmap is accessed later, it'll automatically page back in.

    I don't know about your box, but mine (Athlon XP2000+) can decompress JPEGs at a rate of around only 3MB per second. My disk drives, OTOH, are a hell of a lot faster than that.

    In other words, letting the OS do its job by tossing the images onto swap when necessary strikes me as a much better strategy than constantly sucking up CPU decompressing every image every time it's used just in case the memory might be needed.

    People worry too much about VMEM, IMHO. If I write a program that allocates 1G of memory, but then spins around using only 10k for the next hour, it'll have basically zero impact on the OS. Only ~10k if real RAM is actually getting used.