I got this output: root@fast [~]# top top - 21:50:27 up 9:31, 1 user, load average: 9.39, 9.51, 9.12 Tasks: 249 total, 1 running, 247 sleeping, 0 stopped, 1 zombie Cpu(s): 3.0%us, 0.3%sy, 0.0%ni, 49.4%id, 46.8%wa, 0.2%hi, 0.3%si, 0.0%st Mem: 8182280k total, 8136840k used, 45440k free, 119352k buffers Swap: 8388600k total, 35280k used, 8353320k free, 5111496k cached In Cpu Usage what does it mean ? 49.4%id, 46.8%wa ? what is %id and what is %wa ?
As Janak said, 'wa' is IO Wait. Basically your CPU is having to wait on the disk drive, you should probably look into what is hogging your disks.
is there any way to track which processes takes IO ? like which processes using disks so much ? I am having RAID on server so I am very surprised that server using CPU resources for IO.
Is it builtin RAID or software RAID? If it is software RAID, then that is understandable. If not, then you have bigger problems. Looks like you need more memory. My goodness that machine is a BEAST though! At least, I do not understand why you are using swap space for any thing... Even though you have a little bit of memory left...