What's an oplock_break?

[Rob Naccarato]

On Wed, 7 Oct 1998, Andrej Borsenkow wrote:


> > I've been seeing these in my logs files ever since I upgraded to 1.9.18p10
> > and turned on oplock support for users' home directories:
> >
> > --snip --
> > 1998/10/07 10:05:44 oplock_break: receive_smb timed out after 30 seconds.
> > 1998/10/07 10:05:44 oplock_break failed for file Start Menu/Open Office
> > Document.lnk (fnum = 14, dev = 808446, inode = 45cb8).
> > 1998/10/07 10:05:44 oplock_break: client failure in break - shutting down
> > this smbd.
> > --snip --
> >
> 
> Are you sure you are running 1.9.18p10? Notably, this was the problem,
> triggered by WinNT 4.0 Workstation bug. Workaround was available somewhen
> about 1.9.18p4.
> 

I am 100% positive that the server is running 1.9.18p10.  I don't have any
WinNT clients.  All my clients are Win95.  Could this be an Explorer.exe
problem instead?

> The problem is, sometimes WinNT 4.0 Workstation tries to rename the file,
> for which it holds oplock (locking request). SAMBA server tries to first to
> notify this workstation, that file is already opened and it should release
> the lock. Unfortunately, NT never answers ... SAMBA assumes, the client has
> died, and closes connection.
> 
> It happens only on NT Workstaion - not on Server. The easy way to reproduce
> it was (in Explorer) - New -> New Word Document -> tip something in and say
> "Exit" in Word -> answer "Yes" when asked if you want to save changes. Word
> "hangs". Or, yes, it was Word 97.
> 
> > Is this something to be worried about?
> 
> Yes. Most probably, you don't run the latest version. Recheck.

See above.

> 
>  What effects does this have on
> > client-side performance?
> 
> Well, immediate effect is these nasty delays. After server died, client
> normally reconnects and finishes operation. It may have some impact on
> mutual locking between several tasks.
>  Note that I have set keepalives = 30 in my
> > smb.conf file - could that be the cause?
> 
> No.

That's a relief, at least.

So, in summary, I am running 1.9.18p10 and I don't have any WinNT clients.
What's going on here?

Rob Naccarato           "Civilized men are more discourteous than savages
Sys Admin               because they know they can be impolite without
Sheridan College        having their skulls split, as a general thing."
Oakville, Ont. Canada                      - Robert E. Howard