Re: [Exim] speed of lookup types

On Sun, Mar 14, 2004 at 11:05:20PM -0800, Tom wrote:
> > Different expenses. Better to use PostgreSQL (or at least INNODB on
> > mysql) which isn't locking.
> > You're competing with two problems on flat file DB's:
> > Locking
> > Linear search speeds
>
> A dbm style lookup (BDB) will not lock or require a linear search. dbm
> files are indexed. And usually you just rebuild the entire file and
> rename it over the old file with exim_dbmbuild, so locking is not an
> issue.

Incorrect. In Berkley DB (at least before 4.x) you need to lock the
entire file in order to write to it. I don't know the case after 4.x it
may have changed.