I use debian linux debian 6 (Linux 2.6.32-5-amd64 on x86_64) and if I query the process stat list (ps or top) every process has zero cpu usage. If I query the apache stat there is also zero cpu usage.
I have installed every upgrade package but the problem is still on. And I forgot to mention that the server has load. So the cpu usage mustn't be zero!
This is a HP server with SAS RAID1, 12GB ram and one Intel(R) Xeon(R) CPU E5504 @ 2.00GHz, 4 cores. (not virtual)
I think there must be some missconfigure or some file has damaged or something. I'm not linux specailist so I don't know what can cause this.