[wplug] Mousewheel and your CPU

[Carmelo Edwrd Piccione]

On Wed, 20 Nov 2002, Edward Walter wrote:

> I've encountered similar problems.  It shouldn't be a resource / speed
> issue.  The box is a p4 1800 w/ 512 Mb ram.  The disks aren't a bottleneck
> either... hardware raid 5 - scsi2 / lvd.  I get the skips when selecting
> text rather than scrolling with the mouse wheel.  I've seen this in both
> gnome and kde using mozilla and konqueror.  It seems to spike the cpu just
> long enough to disrupt xmms.  I've configured xmms to run suid root and
> with realtime priority.  I've also increased the buffer sizes it's using.
> Neither of these seem to have much affect though.  I'd rather not have to
> rebuild my kernel just to get the performance I should have anyway.  Any
> other suggestions?
> -Ed

Hey Ed, I can't stress how unbelievably better linux runs with the
premptible kernel patch. Do yourself a favor and try it
(not to mention that kernel 2.5 has ridiculous speed improvements with memory
management) Also, one more issue I've noticed is that sometimes your hard drive flags aren't set for
optimization.

hdparm -c1 -d1 -m8 -k1 /dev/hda
will set your ide driver "a" to 32 bit mode, dma on, multisectors to 8
(also can try 16), and the k switch saves the settings (if the hard drive for some
reason does a reset). To keep these parameters you can throw it in any
boot file such as /etc/rc.d/rc.local. There are other performance
switches, just type hdparm to find them out. To check if something was
already enabled, hdparm -d /dev/hda returns the flag of dma for example.

Finally to test the increase of performance, you can benchmark using
hdparm -tT /dev/hda

PS: some hard drives run erratic with -c1, if this happens try -c2 or -c3
instead

Carm