Re: High CPU usage (up to server hang) under heavy I/O load

Alan Cox
2004-08-13T23:18:39Z

On Gwe, 2004-08-13 at 15:01, Sylvain COUTANT wrote:
> I have a problem with one server (DELL, 1 TB RAID5 + RAID0, Bi-Xeon, 8 GB
> RAM) which, sometimes, goes mad when the I/O pressure gets too high. We use
> this server as a VMWare server and as a backup server (200 GB are dedicated
> to the backup part). We have run full hardware diags and checked every
> software that runs on the system. We have been able to reproduce the problem
> once without having launched the VMWare server (so I believe this software
> is not responsible for the problem).
>
> We have tested kernels 2.4.22 and 2.4.26. The server is running under Debian
> Woody.

Is your raid controller 64bit capable ? If you can I'd also go to a 2.6
kernel for anything > 1Gb, and definitely > 4Gb of RAM. The differences
are astounding although if your PCI I/O hardware cant do 64bit access
your box will suck whatever kernel 8)