[kvm-devel] performance with guests running 2.4 kernels (specifically RHEL3)

[David S. A. <da...@ci...>]

I have been looking at RHEL3 based guests lately, and to say the least the
performance is horrible. Rather than write a long tome on what I've done and
observed, I'd like to find out if anyone has some insights or known problem
areas running 2.4 guests. The short of it is that % system time spikes from time
to time (e.g., on exec of a new process such as running /bin/true).

I do not see the problem running RHEL3 on ESX, and an equivalent VM running
RHEL4 runs fine. That suggests that the 2.4 kernel is doing something in a way
that is not handled efficiently by kvm.

Can someone shed some light on it?

thanks,

david