Re: [exim] dbm vs. text lookup - when to I switch to dbm?

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Author: Tony Finch
Date:  
To: Marc Perkel
CC: exim-users
Subject: Re: [exim] dbm vs. text lookup - when to I switch to dbm?
On Mon, 10 Jan 2005, Marc Perkel wrote:
>
> A lot - I'd guess just under a million.


At that volume thinking about this kind of optimisation might be
worthwhile. If the file is less than 4K then optimising the format is
probably a waste of time. DBM files probably have a higher cutover point
than CDB files. I assume you've already implemented basic disk
optimisations like no_message_logs and no_write_rejectlog.

> But - the question is also - I have some text lists with 4 entries so I assume
> that 4 is quicker with just a text search. I assume probably 100 is faster in
> a DB search. Where is the breaking point? 25 - 50?


If you really care, benchmark it.

Tony.
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