Messages in this thread | | | Date | Thu, 11 Jan 2007 14:06:54 +0100 | From | Martin Mares <> | Subject | Re: O_DIRECT question |
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Hello!
> Maybe you need to say why you want to use O_DIRECT with its terrible > performance?
Incidentally, I was writing an external-memory radix-sort some time ago and it turned out that writing to 256 files at once is much faster with O_DIRECT than through the page cache, very likely because the page cache is flushing pages in essentially random order. Tweaking VM parameters and block device queue size helped, but only a little.
Have a nice fortnight -- Martin `MJ' Mares <mj@ucw.cz> http://mj.ucw.cz/ Faculty of Math and Physics, Charles University, Prague, Czech Rep., Earth Linux vs. Windows is a no-WIN situation. - 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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