Re: [cobalt-users] DISK I/O Performance, RaQ3i and RAID0

[flash22@xxxxxxx]

On Thu, 15 Feb 2001, Peter R. Hubberstey wrote:
[only 3 days behind, it's catching up ;]
> Hello all.
> 
> Running a raq3 as a makeshift cruddy mail server and the syslogd just takes
> up SO much CPU time it's untrue.
> 
> I've done loads of things such as reducing log levels, rotating the logs
> more frequently etc etc but it's still much the same.  It's basically
> handling TOO much mail and the IO performance is as slow and lumpy as a
> 1920's tractor... you know - all thick and muddy...

did you try adding a dash in front of the filename in syslog conf? this
disables synchronous updates to the log file (eg maillog) which usually
increases sendmail speed by 500% or so -/

Worst case side effect, if the machine crashes in the middle of a mail
xfer you loose a few lines of log file....

None the less, don't underestimate the load mail can place on a machie ;)

> make a /etc/raidtab describing a RAID0 device /dev/md0 using /dev/hda3 and
> *say* /dev/hdc1

The only problem with that is you end up with an asymmetric raid
configuration, because you have non-raid partitions on hda that will be
used sometimes, you won't get quite as much as you expect, tho it should
help ...

> Does anyone know if RAID0 support was compiled into the 2.2.14C5 kernel???
> I've checked 2.2-14 source and it is there...

/proc/sys/dev should have md if the kernel has raid support...

> 
> Any thoughts very very very greatly appreciated

Absolutely tell us if you do this and it works well :)

gsh