Samba sharing an NFS mount point

nfs mount option nolock worked for me.

edit: you can add the 'nolock' to mount options in fstab, or 'mount -o nolock,remount /mount_path' to mount it on demand. I had an issue with samba creating a mount on an nfs volume and it created infinite open connections until I added this mount option.

The Samba manual mentions that re-exporting a NFS mountpoint over Samba does not work correctly. NFS is not 100% POSIX compatible, so some things work differently than what Samba expects.

I.e. you should run Samba on the same server where you run the NFS service, exporting the local disks directly.

Did you add the tuning fix to smb.conf?:

socket options = TCP_NODELAY IPTOS_LOWDELAY

The SAMBA howto gives more options and explanations: http://us1.samba.org/samba/docs/man/Samba-HOWTO-Collection/speed.html

The socket option TCP_NODELAY is the one that seems to make the biggest single difference for most networks. Many people report that adding socket options = TCP_NODELAY doubles the read performance of a Samba drive. The best explanation I have seen for this is that the Microsoft TCP/IP stack is slow in sending TCP ACKs.