Michael Darling wrote:
> Eric, for the numbers you provided, are you using a single drive,
> software raid, or hardware raid? If a hardware raid, is it a 3ware card?
it's a simple partition on a sata drive.
> I hadn't seen the nobarrier mount option before. Using that changes
> sequential creates from about 190/second to about 2500/second, and
> changes sequential deletes from about 170/second to about 3700/second.
I wasn't recommending, necessarily, that you use it, but was just
looking for bottlenecks...
> I don't yet have a BBU for the 3ware card, but would certainly get one
> if we go with the 3ware card before we start putting real data on the
> raid. Am I right that with a BBU unit and a battery backup for the
> server as a whole, that nobarrier would be safe to use?
>
> Not using nobarrier, but using logbsize 256k changes sequential creates
> from about 190/second to about 270/second. So, it's an improvement, but
> no where near where a software raid performs (1600/second) or where the
> hardware raid performs with nobarrier.
Default mkfs & mount w/ 256k logbufs:
xfs,256k logbuf: 1353/s
> On Thu, Apr 24, 2008 at 1:33 AM, David Chinner <dgc@xxxxxxx
> <mailto:dgc@xxxxxxx>> wrote:
> > So I played with this a little on 2.6.25, on plain partitions.
> >
> > I saw similar numbers; for example, sequential creates:
> >
> > ext3: 23698/s
> > xfs: 319/s
> > xfs,nobarrier: 4478/s
>
> And with logbsize=256k?
>
> Cheers,
>
> Dave.
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