NFS & Zimbra performance problem

[fab]

Few days ago we moved our ZCS install (the whole /opt/zimbra directory) from a Xsan volume to a FAS 2050 storage shared via NFS.
We have more than 3000 users.
ZCS used to work well on Xsan but now it is almost unusable because we have a Java process (invoked by zmmailboxd) eating almost all the cpu on the mailbox server.
Any advice?

[phoenix]

Few days ago we moved our ZCS install (the whole /opt/zimbra directory) from a Xsan volume to a FAS 2050 storage shared via NFS.
We have more than 3000 users.
ZCS used to work well on Xsan but now it is almost unusable because we have a Java process (invoked by zmmailboxd) eating almost all the cpu on the mailbox server.

That's hardly surprising using NFS.

Any advice?

Move it to a RAID10?

[fab]

I have read that zimbra wiki post about not using NFS, but I also read about other users here using it with a Netapp storage, that should have a robust NFS implementation being what they do for a living ... maybe that the NFS implementation on Mac OS X Server 10.5.8_x86 is not so robust.
What are we supposed to do with such a storage if we can't use it for a mailbox server?
What about iSCSI?
I know that is not natively supported by Mac OS X, but there is a 3rd-party driver here:
Studio Network Solutions - Download iSCSI Initiator for Mac OS X
that I tested once on our Xserve but its performances didn't look better that those of Xsan.

[phoenix]

Well if you want the best performance don't take my word for it, feel free to search the forums for additional user recommendations. The wiki article is based on Zimbra experience of testing the product with NFS (plus the other recommendations in that article) and your best performance is going to be with a RAID10 configuration.

[fab]

Well if you want the best performance don't take my word for it, feel free to search the forums for additional user recommendations. The wiki article is based on Zimbra experience of testing the product with NFS (plus the other recommendations in that article) and your best performance is going to be with a RAID10 configuration.

Thanks for your answers.
Our Netapp is actually configured with their native RAID 6 DP (diagonal parity), did you mean to configure the Netapp filer with RAID 10?
We just have an empty drive slot on our server, thus an external storage is mandatory, also for HA reasons.
I have also found this press release on both the Zimbra and Netapp web sites:
Zimbra - Press Release
what about it?