Re: DB calls vs Session solution

On Mon, Mar 13, 2006 at 03:30:18PM +0100, Jochem Maas wrote: > I just realized I must be evil ;-) Arn't we all :) > secondly I take 'the cache your db results in the session' > to an extreme - by shoving serialized ResultSet objects (with all > results in tow of course) into shared memory by way of the APC > extension... this is of course evil because Rasmus' says "don't > stick objects in the APC cache you fools" (I paraphrase ;-), > the server in question is a single site machine with lots of crazy > marketing induced queries - by caching _all_ select queries I have > reduced the load on average from 5+ to 0.5+- Ah, see this is a bit different, and goes along the theory of a cost has to come from somewhere, and in this case you have memory to use and abuse. The problem with relying on a third party solution, whether it be APC's cache or MySQL's cache, you end up having your application dependent on them to work under heavy load. But then again, if a site is rather busy custom solutions will be needed, and requirments to run the site become greater. I'd like to see google/yahoo ported to some server(s) easily :) > > out of interest, Curt when you say 25 requests a second exactly what > kind of requests? I mean 25 request each second on a php file that queries > a DB with lots of LEFT JOINs, etc is going to require a pretty heavy > piece of iron no? (at least more powerful than anything I can get my hands > on in general.) Yes, 25 requests per the webserver, aka each php file. Since you evily top posted i would guess that one of my suggestions, in the thread, was to try to design something that didn't have a left join. If I had relied on left joins to join the data i need to get the site working my apache's 'current request being processed' of 182 would be bringing any P4 with hyperthreads to its knees :) I think as this topic is enfolds, the key thing is either to make your queries as fast as possible (using good indexing), flatten a structure to provide speed, or use a cache system. > > PS Curt thanks for the braindump - you got me thinking again! Thats what I'm here for :) > > Curt Zirzow wrote: > >On Fri, Mar 10, 2006 at 02:10:54PM +0200, Thomas wrote: > > > >>Hi there, > >> > >>Quick question on performance: > >> > >>I have got some expensive sql queries (doing lots of LEFT JOINS) that > >>result > >> ... > [clip top posted info] Curt -- cat .signature: No such file or directory