Version: Red Hat Enterprise Linux Server release 6.2 (Santiago)

Scenario:

I mount a directory using:
mount -o nosuid,rw 130.159.235.238:/mount/dir /dir
I then try to create a 1G file in /dir and it takes 95s

[root@back data]# date;dd if=/dev/zero of=file.txt count=1024 bs=1048576;date
Wed Jun 6 14:36:02 BST 2012
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 95.8464 s, 11.2 MB/s
Wed Jun 6 14:37:37 BST 2012

If I do the same commands on a different server (Redhat 4.8) but to the same NFS mount then its only 14s

[root@natella data]# date;dd if=/dev/zero of=file.txt count=1024 bs=1048576;date
Wed Jun 6 14:41:03 BST 2012
1024+0 records in
1024+0 records out
Wed Jun 6 14:41:17 BST 2012

All servers are on the same network and have the same hardware spec etc Why is it so slow on the 6.2 server ?

11.2 MB/s = 100Mb/s network equipment on the way (or negotiated this speed), and faster must has 1Gb/s. Check with "ethtool".

ref:
http://www.linuxtopia.org/online_boo...nt-config.html

or may be

http://www.cyberciti.biz/faq/centos-...ilesd-for-nfs/