Messages in this thread | | | Date | Fri, 8 Jul 2005 08:44:28 +0800 | From | Coywolf Qi Hunt <> | Subject | Re: Swap partition vs swap file |
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On 7/8/05, Andrew Morton <akpm@osdl.org> wrote: > Mike Richards <mrmikerich@gmail.com> wrote: > > > > > > Given this situation, is there any significant performance or > > > > stability advantage to using a swap partition instead of a swap file? > > > > > > In 2.6 they have the same reliability and they will have the same > > > performance unless the swapfile is badly fragmented. > > > > Thanks for the reply -- that's been bugging me for a while now. There > > are a lot of different opinions on the net, and most of the > > conventional wisdom says use a partition instead of a file. It's nice > > to hear from an expert on the matter. > > > > Three more short questions if you have time: > > > > 1. You specify kernel 2.6 -- What about kernel 2.4? How less reliable > > or worse performing is a swapfile on 2.4? > > 2.4 is weaker: it has to allocate memory from the main page allocator when > performing swapout. 2.6 avoids that. > > > 2. Is it possible for the swapfile to become fragmented over time, or > > does it just keep using the same blocks over and over? i.e. if it's > > all contiguous when you first create the swapfile, will it stay that > > way for the life of the file? > > The latter. Create the swapfile when the filesystem is young and empty,
I guess/hope dd always makes it contiguously.
> it'll be nice and contiguous. Once created the kernel will never add or > remove blocks. The kernel won't let you use a sparse file for a swapfile. >
-- Coywolf Qi Hunt http://ahbl.org/~coywolf/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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