Re: 2.6.4 ext3fs half order of magnitude slower than xfs - bulkwrite

From: Andrew Morton
Date: Thu Mar 18 2004 - 00:45:27 EST


Matthias Andree <matthias.andree@xxxxxx> wrote:
>
> Andrew Morton:
>
> > It should be possible to generate a simple testcase which demonstrates this
> > problem on that machine. Is that something you can do?
> >
> > From your description, write-and-fsync.c from
> >
> > http://www.zip.com.au/~akpm/linux/patches/stuff/ext3-tools.tar.gz
> >
> > would be a good starting point.
>
> I've run "write-and-fsync -m SIZE -f SOMEFILE" where size is given in
> each section and SOMEFILE was chosen for some real-life but idle file
> system. I hope this is what you meant. I did one run per test.

Cannot reproduce, sorry. Kernel is 2.6.5-rc1, disk is a "MAXTOR 6L080J4"


time write-and-fsync -m 256 -f foo

writeback caching off, ext3/ordered:
write-and-fsync -m 256 -f foo 0.00s user 1.19s system 4% cpu 24.247 total

writeback caching off, XFS:
write-and-fsync -m 256 -f foo 0.00s user 0.57s system 2% cpu 24.041 total

writeback caching on, ext3/ordered:
write-and-fsync -m 256 -f foo 0.00s user 1.16s system 14% cpu 8.169 total

writeback caching on, XFS:
write-and-fsync -m 256 -f foo 0.00s user 0.58s system 8% cpu 6.950 total
write-and-fsync -m 256 -f foo 0.00s user 0.54s system 6% cpu 8.109 total
write-and-fsync -m 256 -f foo 0.00s user 0.55s system 5% cpu 10.057 total
write-and-fsync -m 256 -f foo 0.00s user 0.56s system 8% cpu 6.870 total

(quite some variability in XFS)


So... Maybe you could test some other disks or something?
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/