>> I'm sure I remember reading in the exim manual that dbm searches are
>> cached (although I can't find it now) so my gut feeling is that a dbm
>> search will always be faster regardless.
>
>Only within one run of Exim. It has been hypothesized that you need more
>than a file buffer's worth of list to make it worth using dbm, but I
>don't actually know.
The operating system does more than enough caching to eliminate any
significance to the performance difference between dbm and a binary
search except for aliases files in excess of perhaps 512K. There is
a performance difference, of course, but it is dwarfed by the overall
processing involved in mail delivery.
--
Ronald S. Karr
tron |-<=>-| tron@???
