Re: ZFS perfomance regression in FreeBSD 12 APLHA3->ALPHA4

From: Mark Johnston <markj_at_freebsd.org>
Date: Fri, 7 Sep 2018 12:05:23 -0400
On Fri, Sep 07, 2018 at 04:34:23PM +0300, Subbsd wrote:
> > > > On 2018-09-05 10:04, Subbsd wrote:
> > > > > Hi,
> > > > >
> > > > > I'm seeing a huge loss in performance ZFS after upgrading FreeBSD 12
> > > > > to latest revision (r338466 the moment) and related to ARC.
> > > > >
> Unfortunately, I can not conduct sufficiently serious regression tests
> right now (e.g through benchmark tools, with statistics via PMC(3),
> etc.). However, I can do a very surface comparison - for example with
> find.
> tested revision: 338520
> loader.conf settings: vfs.zfs.arc_max="128M"
> 
> meta strategy ARC_STRATEGY_META_BALANCED result:
> 
> % time find /usr/ports -type f > /dev/null
> 0.495u 6.912s 7:20.88 1.6%      34+172k 289594+0io 0pf+0w
> 
> meta strategy ARC_STRATEGY_META_ONLY:
> % time find /usr/ports -type f > /dev/null
> 0.721u 7.184s 4:57.18 2.6%      34+171k 300910+0io 0pf+0w
> 
> So the difference in ~183 seconds.
> Both test started after a full boot OS cycle.

Seems like a pretty substantial difference.  Is this roughly the same
performance that you had before the upgrade to -ALPHA4?
Received on Fri Sep 07 2018 - 14:05:29 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:41:18 UTC