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

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

Avi Kivity wrote:
> Not so fast...  the patch updates the flood count to 5.  Can you check
> if a lower value still works?  Also, whether updating the flood count to
> 5 (without the rest of the patch) works?
> 
> Unconditionally bumping the flood count to 5 will likely cause a
> performance regression on other guests.

I put the flood count back to 3, and the RHEL3 guest performance is even
better.

> 
> While I was able to see excessive flooding, I couldn't reproduce your
> kscand problem.  Running /bin/true always returned immediately for me.

A poor attempt at finding a simplistic, minimal re-create. The use case
I am investigating has over 500 processes/threads with a base memory
consumption around 1GB. I was finding it nearly impossible to have a
generic re-create of the problem for you to use in your investigations
on CentOS.

Thanks for the patch.

david