How Samba let us down

[Jay Ts]

Chris de Vidal wrote:
>Mathew McKernan <mathewmckernan at optushome.com.au> wrote:
> > By the look of it, the reason why it is so slow is
> > the fact that you may not be running a WINS Server.
> 
> While this is a great way to increase speed,
> A. It's plenty fast on the NT, Netware, and other
> Samba servers.  In fact, the slowness appears to be
> totally isolated to the new Samba server.
> B. The slow browsing is on the hard drive once
> connected to the server, not cruising network
> neighborhood where WINS would be most effective.
> C. Our primary problem is data corruption, not
> performance, though they could be related.

It might be that the lack of WINS is causing massive
network traffic at odd moments, as systems engage
in broadcast name resolution. It is a good idea to
avoid this sort of thing whenever possible. Perhaps
the contention on the net is causing accesses to
your Samba server to timeout.  (Just a thought.)

> The corruption might be related to oplocks.  I'm doing
> research.
> 
> Is it safe to disable kernel, regular, and level2
> oplocks if we're not doing any linux-side read/writes?

kernel oplocks are for synchronizing SMB clients and
local Unix processes. If you have no processes on linux
accessing the files, then it's probably safe to disable them.
But, if you are using Linux, the only way you should have
kernel oplocks enabled in the first place is if you have
installed the kernel ACL patch, or are running XFS filesystem.
Some newer distributions come with the ACL patch installed,
I think.  What version of Linux are you running?

> Have you seen better documents on implementing Samba
> WINS than what is on samba.org or in /usr/share/doc?

Are you Running Linux from a source or binary distribution?
If you've compiled from source, your Samba docs would be
in the source tree (docs directory) and you would have the
first edition of Using Samba there as well.  There is a
whole chapter on name resolution and browsing. The information
there is old, but mostly correct.

Since what you wrote above possibly suggests you didn't see
that, I suspect you might be running a binary distribution,
and maybe it's old ... so, what version of Samba are you
running?  Try compiling a new version (2.2.6, for example).
Older versions had bugs, and I've seen the same behavior that
you describe with earlier releases of 2.2.x.

Jay Ts
author, Using Samba, 2nd edition