Hi,

I have a big server with 24 Disk on 2 3ware card.

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.

[root@NFS /]# vmstat 1 procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu------ r b swpd free buff cache si so bi bo in cs us sy id wa st 0 1 112 9592 7140 1879496 0 0 621 1180 6 2 0 2 86 11 0 0 9 112 10668 7148 1877760 0 0 84 21600 1926 454 0 3 49 49 0 1 3 112 9308 7156 1879092 0 0 1400 1580 2123 2009 0 2 50 48 0 0 0 112 9432 7156 1879476 0 0 3664 0 2275 2862 0 3 81 17 0 0 1 112 9212 7172 1879588 0 0 2196 32 2132 2293 0 2 66 32 0 1 0 112 9848 7180 1878864 0 0 1268 4168 1852 1934 0 2 84 14 0 0 7 112 11208 7180 1876936 0 0 92 13124 1339 355 0 2 50 48 0 0 0 112 10708 7188 1877512 0 0 628 16 1552 1014 0 1 84 16 0 0 1 112 10344 7188 1878044 0 0 472 0 1334 721 0 1 89 10 0 0 1 112 10372 7196 1878136 0 0 1936 32 2268 2850 0 2 50 48 0 0 0 112 10336 7192 1878312 0 0 2220 0 2308 2966 0 2 51 47 0 0 0 112 9716 7200 1879012 0 0 696 28 1484 885 0 1 89 11 0 0 2 112 9400 7200 1879280 0 0 236 0 2112 5819 0 8 75 18 0 0 0 112 9980 7196 1878816 0 0 1360 20 1840 1743 0 1 83 15 0 0 15 112 9168 7196 1879580 0 0 768 0 1423 728 0 1 91 9 0 0 0 112 10756 7200 1877752 0 0 4068 32 2788 4225 0 4 70 26 0

I have tuned nfs server with this option :

RPCNFSDARGS="-N 2" RPCNFSDARGS="-N 4" MOUNTD_NFS_V3="yes" RPCNFSDCOUNT=160

about the file system, i use ext4 on LVM partition.

Do you have any idea about that.

Fabien FAYE RHCE www.generationip.com Free network tools & HOWTO for centos and Redhat