Re: [Sqlgrey-users] impressive results from using memcached

[Michael S. <Mic...@lr...>]

Hi Dave,

thanks for your tip. However I do not store SELECT statements in
memcached, but only the relevant information, e.g.

Feb  5 16:41:09 lxmhs25 lrzgrey_test[2773]: grey: _make_key: digest=jrVgwImoOnIasrhipprBaw from from_awl:193.220.212.39,technical_support_op_291fv,finanzen.sparkasse.de

And I use a carefully calculated expiration time, therefore the entry in
the cache times out at the same time as a entry in a AWL.

And as you can see, I get a tremendous hit rate for the states unknown und
throttle. This was my main goal. Getting hits for the AWLs is fine, but
for the overall performance not so relevant at least in our case.


On Mon, 5 Feb 2007, Dave Strickler wrote:

> Michael,
>

> Be careful about the SELECT statements you store hits on in memcached.
> Many SQLGrey SQL statements use a time parameter, and thus, by their
> nature, will never be used again (eg. SELECT * FROM table WHERE utstamp
> > $now).
>
> I found when using memcached with SQLGrey that I had to alter the SQL
> calls so a result stored in memcahed was not 'time sensitive". Of
> course, the makes SQLGrey not as perfect at detecting exact times for
> expired records, etc, but I felt this was a worthwhile tradeoff.
>
> I am currently getting a 40%-50% memcached hit rate with my alterations.
>
> Dave Strickler
> MailWise LLC
> 617-933-5810 (direct)
> www.mailwise.com ( http://www.mailwise.com/ )
> "Intelligent E-mail Protection"

Michael Storz
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