Changing subsystem priorities

Changing subsystem priorities

[Michael T. Babcock]

I was looking at the performance of one of my systems the other day and 
realised that it was often slowed by processes requesting disk I/O 
while other (often unrelated) processes were waiting to send network 
packets.  For the sake of thinking out loud, would it be possible to 
allow priority changes on a subsystem basis within the kernel?  That is 
to say, either tell the kernel that handling disk io is less important 
than handling network io (or vice versa) or perhaps that processes 
waiting for disk io be given their timeslices a little 'later' so that 
other non-disk-bound processes get a few more?  I understand that this 
is entirely based on the priorities I have for one sserver but other 
people may wish to accomplish similar things with different priorities. 
 Is this type of scheduler adjustment possible or even desirable?

For what its worth, the system in question is running 2.2.20 until I
find stable drivers for my DPT SmartRaid V controller for 2.4.x.
-- 
Michael T. Babcock
CTO, FibreSpeed Ltd.     (Hosting, Security, Consultation, Database, etc)
http://www.fibrespeed.net/~mbabcock/

RE: Changing subsystem priorities

[Bonds, Deanna]

> -----Original Message-----
> From: Michael T. Babcock [mailto:mbabcock@fibrespeed.net]
> 
> For what its worth, the system in question is running 2.2.20 until I
> find stable drivers for my DPT SmartRaid V controller for 2.4.x.
A little off topic, but since I am the maintainer of the dpt_i2o driver,
what do you find unstable about the 2.4.* version.  It has been through our
qualification several times and is now imbedded in the kernel.  If you know
of any instability please let me know so I can fix it.

Deanna