Hello On Thu, 2006-06-08 at 13:00 +0200, Jens Axboe wrote: > On Wed, May 24 2006, Hans Reiser wrote: > > Tom Vier wrote: > > > > >On Tue, May 23, 2006 at 01:14:54PM -0700, Hans Reiser wrote: > > > > > > > > >>underlying FS can be improved. Performance results show that the new > > >>code consumes 40% less CPU when doing "dd bs=1MB ....." (your hardware, > > >>and whether the data is in cache, may vary this result). Note that this > > >>has only a small effect on elapsed time for most hardware. > > >> > > >> > > > > > >Write requests in linux are restricted to one page? > > > > > > > > > > > It may go to the kernel as a 64MB write, but VFS sends it to the FS as > > 64MB/4k separate 4k writes. > > Nonsense, Hans refers to generic_file_write which does prepare_write copy_from_user commit_write for each page. > there are ways to get > PAGE_CACHE_SIZE writes in one chunk. > Other file systems have been doing it for years. > Would you, please, say more about it. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] 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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