[CentOS-virt] VM Slowness

Mon May 20 03:54:44 UTC 2013
compdoc <compdoc at hotrodpc.com>

I hope this in the right list, but I was wondering if someone could help me
with a VM I have that has lately started having problems. It had been
running for years without problems. It's possible an update is causing this,
but I can't say.

The VM is running CentOS 5.8 and after a time, the machine begins to slow
down. Things like pings or running commands lag. If I reboot the VM, it runs
normally for at least a few hours, but it eventually slows again. 

I've tried changing the VM's virtio devices to standard devices like IDE and
e1000, but it makes no difference. Currently its running virtio.

Top shows that nothing is taking up significant cpu time, but even running
top takes several seconds for it to open. The system is slow now, but top
shows:

top - 21:39:48 up 1 day,  5:27,  1 user,  load average: 0.93, 1.37, 1.12
Tasks: 177 total,   1 running, 176 sleeping,   0 stopped,   0 zombie
Cpu(s):  0.3%us,  0.3%sy,  0.0%ni, 98.6%id,  0.9%wa,  0.0%hi,  0.0%si,
0.0%st
Mem:   2075016k total,  1484624k used,   590392k free,    64336k buffers
Swap:  4128760k total,       12k used,  4128748k free,   981368k cached

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND

 4124 root      20   0  2444 1080  812 R  0.1  0.1   0:00.03 top

    1 root      15   0  2176  692  604 S  0.0  0.0   0:02.46 init

    2 root      RT  -5     0    0    0 S  0.0  0.0   0:00.39 migration/0

    3 root      34  19     0    0    0 S  0.0  0.0   0:00.00 ksoftirqd/0


Any ideas what to look for? Any information I can provide?

Thanks