On Sep 23, 2008 10:16 +0100, Alan Cox wrote: > On Mon, 22 Sep 2008 20:35:23 -0400 > "Theodore Ts'o" <tytso@xxxxxxx> wrote: > > With modern hard drives, reading 64k takes roughly the same time as > > reading a 4k block. So request adjacent inode table blocks to reduce > > the time it takes when iterating over directories (especially when doing > > this in htree sort order) in a cold cache case. With this patch, the > > time it takes to run "git status" on a kernel tree after flushing the > > caches via "echo 3 > /proc/sys/vm/drop_caches", is reduced by 21%. > > > > Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx> > > Acked-by: Alan Cox <alan@xxxxxxxxxx> > > I'm actually suprised that 16 is the magic tuning number you've used and > a bigger one isn't even more of a win I was going to suggest making this at least a #defined constant instead of hard coding the values there. Making it a mount option and/or /proc value would allow further testing. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
