On Mon, Jan 25, 2010 at 8:39 AM, fabien faye <fabien at faye.eu> wrote: > Hi, > > I have a big server with 24 Disk on 2 3ware card. Define 'big'. You're not giving much in terms of memory or cpu specs. > When i write data on my nfs server everything is fine but when i want to read data i have a lot of cpu wait. Okay. Have you looked at any performance tuning or elevator/scheduler adjustments? File system tuning? What have you tried on your own so far to debug this? > about the file system, i use ext4 on LVM partition. Why? Is there a performance reason for you to use ext4 vs ext3? > Do you have any idea about that. Not based on the little information you've provided. It would help for you to supply more detail, and the things you've already looked at. -- During times of universal deceit, telling the truth becomes a revolutionary act. George Orwell