NAS b4000s with SFU 3.0 poor NFS write performance on unix clients

[Thomas Kennerknecht]

Hello,

we have some massiv problems with the write performance on a windows storage server 2003 on a b4000 over NFS in a large environment. Copying or saving large files > 100 MB from unix (HP-UX or AIX) workstations take very long time on the one side (Network load approx. 1-2 % on a GBit LAN). On the other side during copying process, if why try to make a listing in the destination dir ( the NFS share on the storage server) the listing is blocked until the copying process has reached a filesize of approx. 36 MB and multiples. This effects also other unix and windows users who want to make a listing in the same destination directory. So users have to wait seconds till minutes to get the listing. Also other save processes on other unix workstations could be interrupted.
We have discoverd this effect on storage servers b4000s which has installed the NAS Appliance with SFU 3.0 (unpatched and patched with SR3). The current shipments of hp storage servers have installed the NAS Appliance with SFU 3.5. With this newer systems the NFS performance is much better/ok (Network load approx. 25 % on a GBit LAN). The effect of blocking the listing exists also, but the copying process is much faster, so the wait time is much shorter.

A network problem is impossible because the effect happens in different environments.

We also have tested some SFU Registry settings but without any success.

Exists there an upgrade kit from the older NAS Storage Appliance with SFU 3.0 to an NAS Storage Appliance with SFU 3.5 without reinstalling the server.

Please help.

Regards
Thomas

[Monty Phillips]

Hi Thomas,

What mount options are you using when mounting the NFS share on the Unix client? I have found that performance can be greatly increased by making sure 32K block sizes are being used -- i.e. rsize=32768 and wsize=32768.

For example:

Test #1 -- default mount options (i.e. mount :/hp /hp
=========
-- cp /data/testnfs.tar /hp/testnfs.tar
-- time it took for 2GB file copy: 82m13.626s

Test #2 -- mount with 32K block size
=======
-- cp /data/testnfs.tar /hp/testnfs.tar
-- umounted nfs share and mounted with the following options:
mount -t nfs -o tcp,rsize=32768,wsize=32768 : /hp /hp
-- time it took for 2GB file copy: 4m7.663s <------ Huge Difference


- Monty

[cms tsg]

Hi,
Thomas,

MAY I KNOW WHICH SERVICE RELEASE VERSION YOU ARE USING ON NAS B4000,IF YOU ARE USING sr 3.3 .YOU UPDATE SERVICE RELEASE 5.5.


REGARDS
SACHIN