On Thu, 2002-09-26 at 11:41, Bruce Momjian wrote:
> Shridhar Daithankar wrote:
> > I might have found the bottleneck, although by accident. Mysql was running out
> > of space while creating index. So my friend shut down mysql and tried to move
> > things by hand to create links. He noticed that even things like cp were
> > terribly slow and it hit us.. May be the culprit is the file system. Ext3 in
> > this case.
>
> I just added a file system and multi-cpu section to my performance
> tuning paper:
>
> http://www.ca.postgresql.org/docs/momjian/hw_performance/
>
> The paper does recommend ext3, but the differences between file systems
> are very small. If you are seeing 'cp' as slow, I wonder if it may be
> something more general, like poorly tuned hardware or something. You can
> use 'dd' to throw some data around the file system and see if that is
> showing slowness; compare those numbers to another machine that has
> different hardware/OS.
That's a good point. Also, if you're using IDE, you do need to verify
that you're using DMA and proper PIO mode if at possible. Also, big
performance improvements can be seen by making sure your IDE bus speed
has been properly configured. The drivetweak-gtk and hdparm utilities
can make huge difference in performance. Just be sure you know what the
heck your doing when you mess with those.
Greg
