[Samba] samba-2.2.* slow when lock files are on a NFS file system

[jra at dp.samba.org]

On Thu, Sep 19, 2002 at 04:16:43PM -0400, Thomas Schulz wrote:
> Note that I also posted this to comp.protocols.smb under the subject
> Lock files must not be on an NFS file system.  I don't know how closely
> you follow that group.
> 
> On Feb 7 2002 I sent out a message titled
> samba-2.2.2 slower than samba-2.0.7 on Solaris
> where I described a problem where any file access encountered a 3 to 4
> second delay to open the file.  After trying again with samba-2.2.5 and
> finding the same problem, I decided to work harder to find the cause of
> the problem.  What I discovered is that if the lock files are placed on
> an NFS file system, samba-2.2.* takes 3 to 4 seconds to open any file.
> If the lock files are on a local disk then there is no such delay.
> I don't know if this is a bug or just the way it works.  If this is to
> be a restriction, it would be a good thing if this were documented
> somewhere.  Perhaps a note in the man page for smb.conf under the
> lock directory  section.
> 
> Some details on how I have this set up.  We are running Samba on four
> Solaris 8 machines, one of them is a Sparc 10 (a slow machine).  I
> installed Samba in  /opt/local/samba  which is mounted by the automounter.
> This ends up being local on one machine and nfs mounted on the other three.
> In order to keep the log and lock files seperate, I had the following in
> my smb.conf:
> log file = /opt/local/samba/var/logs/%h/log.%m
> lock directory = /opt/local/samba/var/locks/%h
> For samba-2.2.5 I added:
> pid directory = /opt/local/samba/var/locks/%h
> This worked fine for samba-2.0.7.  It was a big problem for samba-2.2.5.
> After changing the lock directory to /var/samba/locks, the 3 to 4 second
> delay went away.
> 
> After doing the above, I realized that the secrets.tdb file in the private
> directory was also on an NFS file system and was being shared by all four
> machines.  This did not seem like a good thing.  I replaced the secrets.tdb
> file with a symbolic link to /var/samba/private/secrets.tdb and found that
> Samba is happy to follow the link and create the secrets.tdb file in
> /var/samba/private.  I expect that this is more correct although I had not
> observed any problem with it the old way.

Do *not* share any of the Samba lock files or the tdb files. This *will*
break Samba.

Also, putting tdb files on an NFS drive is not recommended as tdb makes
heavy use of fcntl locking (slow over NFS).

Jeremy.