SWAP Question?

[Mark van Harmelen]

Hi everyone

On Mon, Aug 10, 2009 at 11:06 PM, Hakan Koseoglu <hakan at koseoglu.org> wrote:

> ....  4GB of RAM is not much
> for a busy database application

Are there any rules of thumb or formulae for a good performant RAM
size  (per core?) for a busy data base server, mySQL is the database
in question. In this scenario, the web app, for a strongly web 2.0
social networking service, is running on different servers and making
requests of the db server.

Sorry if this is a terrible question, no sizing information makes it
hard to answer.  Given the lack of information, is the answer
something algorithmic, like "start at x GB / core, look at the paging
behaviour, and if there is paging, then increase the memory size until
any paging tails off" ? If this is the kind of answer, anyone care to
hazard a guess at x?

thanks
mark