[Samba] Re: Samba 3.0.21 Available for Download

[Jeremy Allison]

On Wed, Dec 21, 2005 at 09:51:57AM -0500, Michael Lueck wrote:
> Gerald (Jerry) Carter wrote:
> 
> >  o Rewrite of CIFS oplock implementation.
> 
> Specifically on the oplock topic:
> 
> Does the fact that the Samba team invested in such a rewrite mean that it 
> is time to reevaluate utilizing oplock capabilities with applications that 
> suggest running with them disabled? Desktop database applications are first 
> in my mind - the Paradox's and Access's of the world. Also accounting 
> packages that share a database file on the server. Peachtree using a 
> Btrieve database on the server.
> 
> Or was this investment in R&D necessary for all of the non database oplock 
> usage, and databases should not attempt to use oplocks?
> 
> Are the capabilities considered cross platform, or were specific platforms 
> targeted - such as Windows 2000 and Linux, but not Windows 98... or 
> something bazaar like that?

The rewrite was done by Volker to make some more operations asynchronous,
in preparation for the fully clustered Samba code (with a distributed filesystem
backend) that is to come. It doesn't change the functionality (other than
I think we pass a few more of the "difficult" Win2K3 compatible tests).

Using oplocks with a backend database application is just a risky business
as everything has to work right. If you have perfect Windows clients (is
that an oxymoron ? :-) and a non-lossy network then it should be ok. But
as always, your milage may vary (and you should check what the DB vendor
recommends - Samba will be no different from a Windows server in this
respect).

Jeremy.