Re: Linux v2.4.19-rc5

[Jens Axboe <axboe@suse.de>]

On Mon, Aug 05 2002, Bill Davidsen wrote:
> On 1 Aug 2002, Steven Cole wrote:
> 
> > Here are some dbench numbers, from the "for what it's worth" department.
> > This was done with SMP kernels, on a dual p3 box, SCSI disk, ext2.
> > The first column is dbench clients.  The numbers are throughput
> > in MB/sec.  The 2.5.29 kernel had a few RR-supplied smp fixes.
> > Looks like for this limited test, 2.4.19-rc5 holds up pretty well.
> > I've also ran this set of tests several times on -rc5 using ext3
> > and data=writeback, and everything looks fine.
> > 
> > Steven
> 
> Call me an optimist, but after all the reliability problems we had win the
> 2.5 series, I sort of hoped it would be better in performance, not
> increasingly worse. Am I misreading this? Can we fall back to the faster
> 2.4 code :-(

try a work load that excercises the block i/o layer alone (O_DIRECT,
raw, whatnot) and then compare 2.4 and 2.5. ibm had some slides on this
from ols, unfortunately I don't know if they have then online.

please don't put too much wait in dbench numbers for this sort of thing
:-)

-- 
Jens Axboe