NFS performance stats on Linux

Linux and Unix-Like Red Hat
1

Hi everyone,

The last two days I'm researching results of NFS operations on Linux, and I noticed some time difference when read and write.
cat /proc/version :

Linux version 2.6.9-42.ELsmp (bhcompile@hs20-bc1-1.build.redhat.com) (gcc version 3.4.6 20060404 (Red Hat 3.4.6-2)) #1 SMP Wed Jul 12 23:27:17 EDT 2006

Here's how I'm testing :

time dd if=/dev/zero of=/opt/home/testfile bs=32k count=16384
  • this will create 512M file. When writing operation is being done, the time reports : 14.962secs; when reading time is 7.313secs.
    I've used mount options as follows :
mount -o vers=3 $my-hosts-here -o rsize=8192,wsize=8192

I was wondering if this behaviour is expected, in not, any comments or suggestions how to overcome this will be highly appreciated. Thanks.

2

After small digging and talk over NFS mailing list, I found out that this behavious is expected, and there are some issues with Red Hat and Dell software.