access idmap cache directly from smbd

[Jeremy Allison]

On Sat, Aug 16, 2008 at 12:18:00PM +0200, Volker Lendecke wrote:
> Hi, Jerry & Simo!
> 
> Attached find two patches that make smbd directly access the
> idmap cache.
> 
> It does widen the interface between smbd and the Samba
> implementation of winbind, but I think it is fully
> compatible with alternative implementations of libwbclient
> like the Likewise one.
> 
> It will speed up Samba operation, because it gets rid of a
> considerable amount of roundtrips to winbind, in particular
> together with the third patch that increases the default
> positive cache timeout to a week.
> 
> If this is not acceptable upstream, we need to discuss a
> separate tdb-based idmap cache for smbd only. I have
> customers where the LDAP server is running at its total
> limit, because they have "hide unreadable" set together with
> many files and Posix ACLs. With every user pressing "f5" in
> a directory, we look up hundreds of gids against LDAP, one
> after the other.  This is a significant performance problem
> in my situation, and I would like to get a relief upstream.

Ok, I've pushed the idmap cache move and the cache
timeout increase for 3.3 as they're obvious goodness.

I'm going to work on the smbd read access to the new
cache next.

Jeremy.