High CPU - kjournald & kblockd - nice level

Brian Hanks bhanks at crackedweasel.org
Wed Jun 23 12:32:08 UTC 2004


> > I have not read your first email, (too lazy atm), but is DMA enabled?
> >
> > hdparm -d /dev/hdx (where x is the drive letter for hd's and
> > cd's/dvd's).
> >
> > In the past if this is not enabled the system performance takes any
> > thing up to a 70% hit in performance.


I embarrassed to admit that this does seem to be the issue.  A while back,
I checked the drive settings, but I must have confused -i & -I.  The drive
(-I) was reporting that it was set to UDMA7, but the (-i) option reported
that no transfer mode was set.   I'm guessing that this is related to the
fact that these drives are SATA.

Any thoughts about UDMA7 vs. MDMA2?  The seem to return similar
performance characteristics, so I'm not sure what the decision point would
be.


> As an afterthought, it may also be worth while running dmesg, and
> looking at the output, check to make sure all chipsets are supported,
> see if there are any error messages being thrown up.
>
> Doug


Nothing odd in dmesg.

-Brian





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