RE: search blocks modify -- why?

[Allan Streib <astreib@indiana.edu>]

On Thu, 17 Apr 2003, Howard Chu wrote:

> > > > Does search by default put the equivalent of a read lock on the
> > > > file, which could block a modify while the search runs?
> > >
> > > Yes.
>
> > And would dbnolocking avoid this?
>
> No.

Can you clarify, then, what is meant by the man page statement that this
directive specifies "that no database locking should be performed."

> back-ldbm in OpenLDAP 2.0 needs all that locking just to prevent itself
> from self-destructing. Most of the back-ldbm indexing bugs have been
> fixed in OpenLDAP 2.1 but we're still not certain that it's 100%
> clean. As such, those locks are still present in 2.1 because we don't
> believe it's safe to use otherwise. This is the price you pay for using
> back-ldbm; this is one reason why back-bdb in 2.1 was written in the
> first place - to allow enhanced concurrency.

Thanks, that helps.  Moving to 2.1 and back-bdb is definitely something I
want to do.

Allan
-- 
"If you understand what you're doing, you're not learning anything."
                                                -- Anonymous