SLES 10 SP4 guest slowly in SLES 11 SP4 host - high si
i have a SLES 10 SP4 guest running slowly in a SLES 11 SP4 host. The guest is running a small web application with a MySQL DB, an apache webserver and some perl scripts. The DB is not really busy, maybe some hundreds requests per day.
But the system performs slowly, especially on a console. Connecting with ssh, e.g. top need between 2 and 3 seconds to refresh its output. It's really not funny to work on the console.
The system has 4 virtual cpus and 8gb of ram. System was before a physical system which was migrated to a vm. The physical system just has 2 cpu's but is running fine. The host is very performanent, 8 cores and 96gb of ram. The host is running fine, no performance problem. And the guest is not a heavy load for it. It's KVM. Vmx flag is set on the host cores.
What i see is that the guest has constantly high si in top.
You see, the system isn't doing much. Very little IO, just a little bit load in user and system context, but much si.
How can i find out from where this si come from ? IIRC correctly, i had this problem already. I updated the system completely to SLES 11 SP4,
and the high si were history. But this was just for test, the system needs to be a SLES 10 SP4.
Maybe the kernel or some modules are the culprit ? I tried to update only the kernel, but it's not possible.
Tons of dependencies.