On Mon 08-07-13 17:22:43, Marco Stornelli wrote:
> Il 08/07/2013 15:59, Jan Kara ha scritto:
> >On Mon 08-07-13 22:44:53, Dave Chinner wrote:
> ><snipped some nice XFS results ;)>
> >>So, lets look at ext4 vs btrfs vs XFS at 16-way (this is on the
> >>3.10-cil kernel I've been testing XFS on):
> >> create walk unlink
> >> time(s) rate time(s) time(s)
> >>xfs 222 266k+-32k 170 295
> >>ext4 978 54k+- 2k 325 2053
> >>btrfs 1223 47k+- 8k 366 12000(*)
> >>(*) Estimate based on a removal rate of 18.5 minutes for the first
> >>4.8 million inodes.
> >>Basically, neither btrfs or ext4 have any concurrency scaling to
> >>demonstrate, and unlinks on btrfs a just plain woeful.
> > Thanks for posting the numbers. There isn't anyone seriously testing ext4
> >SMP scalability AFAIK so it's not surprising it sucks.
> Funny, if I well remember Google guys switched android from yaffs2
> to ext4 due to its superiority on SMP :)
Well, there's SMP and SMP. Ext4 is perfectly OK for desktop kind of SMP -
that's what lots of people use. When we speak of heavy IO load with 16 CPUs
on enterprise grade storage so that CPU (and not IO) bottlenecks are actually
visible, that's not so easily available and so we don't have serious
performance work in that direction...
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR