[Dovecot] XFS vs EXT4 for mail storage

[Stan Hoeppner]

On 5/3/2013 4:31 AM, lst_hoe02 at kwsoft.de wrote:

> If you are going to insult you maybe should write it so non native
> speakers could find it (malarkey).

Sorry Andreas.  I didn't intend that as an insult, merely an expression
of strong disagreement with statements not grounded in facts.

> It is not stunningly that a developer of XFS come out with a setup where
> XFS is the fastest at all.

Dave is even handed with this stuff.  Watch the video.  The pre-delaylog
slides show EXT4 metadata performance really trouncing old XFS by a
*much* larger margin than that of XFS with delaylog over EXT4.  When
delaylog turns the tables the gap is much smaller.  This says more about
how horrible XFS metadata performance was prior to delaylog than how
much better than EXT4 it is today, though it is substantially better
with greater parallelism.
...
> So you have confirmed may suspection that XFS developers will find a
> case where it matters in favour of XFS ;-)

All developers use VMs today for the obvious reason:  It saves so much
time and allows much more work in a given time frame.  Note that for
validation testing of things like barriers they must still use bare
metal since the hypervisors noop disk cache flushes.
...
> I know your history on insisting your are right in any cases, so this is

Then you've obviously missed posts where I've acknowledged making mistakes.

> my last post on this subject. Every reader should try to understand the
> differences on his/her own anyway.

It's never about "being right" but "getting it right".  People require
accurate technical information in order to make technical decisions.  I
provide that when I have the information.  I also try to correct
incomplete, missing, or inaccurate information where I believe it to be
necessary.  You stated that a VM environment eliminates most of the
advantages of any given filesystem, and that's simply not correct.

-- 
Stan