Autor: W B Hacker Fecha: A: exim-users Asunto: Re: [exim] Mail Implementation Design (Update)
Graeme Fowler wrote:
> Hi
>
> On Mon, 2006-08-28 at 17:57 +0800, W B Hacker wrote:
>
>>So - a 'read-mostly' DB, such as CDB, will beat *any* full-house SQL animal for
>>higher read speed, lower resource load - and ultimately, higher reliability.
>
>
> But any RDBMS (whether MySQL, Oracle, PostgreSQL etc etc) will beat a
> "read-mostly" DB for rates of change. In an ISP or volume hosting
> environment, if you want customers to have changes made "live"
> immediately, you can't beat having Exim tied to an RDBMS backend.
Well .. yes, especially the 'heavy lifter' RDBMS (PG, DB2, Oracle) which have
very solid contention management and safe transaction handling.
But even a very active ISP ordinarily has a 'rate of change' that is
insignificantly low compared to, for example, a Point-of-Sale / inventory
control system, theater ticket sales, or banking.
>
> Yes, I know, there are many who do this with atomic, non-blocking,
> non-racing DB exports to various file types on a timed interval basis,
> and that interval can be very low, but if you've already got the hammer
> that Bill mentions... ;-)
>
> Graeme
>
>
ACK. Since we needed it for Zope/Plone anyway...
But I still do not recommend it for general smtp use.