I have several ubuntu 12.04 VMs running on a ubuntu 12.04 KVM host. Those of the virtual machines that are totally idle with no services (except syslog and the other "small" standard stuff of a fresh installation) show a constant load of "0.00 0.01 0.05" in top/htop as average 1/5/15.
When there are "real" applications running, the load averages behave perfectly normal but they never fall below the mentioned values.
While this doesn't affect performance at all and could easily be ignored, it screws up the monitoring graphs in a very annoying way:
(Notice how load15 behaves nicely if 0.05 for a short time in the right half of the pic)
Unfortunately I don't know what diagnostic outputs might be helpful for you, so here's some default stuff:
# top
top - 16:31:01 up 1:05, 1 user, load average: 0.00, 0.01, 0.05
Tasks: 62 total, 1 running, 61 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.2%us, 0.2%sy, 0.0%ni, 99.2%id, 0.5%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1019464k total, 73452k used, 946012k free, 6140k buffers
Swap: 0k total, 0k used, 0k free, 22504k cached
.
# free -m
total used free shared buffers cached
Mem: 995 72 923 0 6 21
-/+ buffers/cache: 43 951
Swap: 0 0 0
.
# iostat -x /dev/vda
Linux 3.2.0-32-virtual (vm3) 11/15/2012 _x86_64_ (2 CPU)
avg-cpu: %user %nice %system %iowait %steal %idle
0.25 0.00 0.65 0.20 0.24 98.66
Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util
vda 0.14 0.12 0.51 0.22 6.74 1.46 22.50 0.02 23.26 20.64 29.30 7.63 0.56
Need something else?
Has anyone ever seen this behavior?
Might this be a bug in kvm/ubuntu/kernel 3.x in the end?
Thanks a lot!
