Memcached processes

[Marcus Bointon]

On 15 Aug 2007, at 06:05, Paul Scott wrote:

> At the moment, the FSIU box has 1GB of RAM, and I am starting 6  
> daemons
> each with 100MB of memory (-m 100). I have tried to play around  
> with the
> settings to try and find a decent configuration, and see that there  
> are
> significant performance differences between them.
>
> Is there a rule of thumb as to how to approach this? Is it better to
> start a single server with 500MB or 5 servers with 100MB each? Is it
> better to assign smaller chunks of memory or larger? At the moment,  
> this
> is in a dev/test environment, and in future we will need to
> productionise it, so this will become an issue that needs to be  
> properly
> documented. In the prod environment, however, I will get a dedicated
> memcached server to handle the caching, but the issue still remains...

Well, the answer is "it depends". One reason for running multiple  
instances on one server is if you have two apps that you want to keep  
separate, not least because you can completely clear one cache  
without affecting the other. Also bear in mind that if you're running  
on a single server, you'll get much, much better performance by using  
APC, eAccelerator, Zend etc, no matter how many daemons you start.  
Memcached isn't worthwhile  until you have more than one server  
running your app (or you need more cache memory than you can get on  
your one server). We have several instances of our smartmessages app;  
For those that are on a single server, we use APC, for those on a  
cluster, we use memcached, and I've written it to support pluggable  
cache back-ends.

Given that your framework will probably be used in similar  
circumstances, it might be a good idea to do the same.

Marcus
-- 
Marcus Bointon
Synchromedia Limited: Creators of http://www.smartmessages.net/
UK resellers of info at hand CRM solutions
marcus at synchromedia.co.uk | http://www.synchromedia.co.uk/