Re: Which hardware ?

On Tue, 17 Jun 2008, Andrew Sullivan wrote:

> A running JVM is necessarily going to use some memory, and that is
> memory use that you won't be able to factor out properly when developing
> models of your database system performance.

Now you've wandered into pure FUD.  Tuning maximum memory usage on a Java
app so you can model it is straightforward (albeit a little confusing at
first), and in most cases you can just sample it periodically to get a
good enough estimate for database tuning purposes.  JVMs let you adjust
maximum memory use with -Xmx , and if anything the bigger problem I run
into is that using too much memory hits that limit and crashes Java long
before it becomes a hazard to the database.

This is a system with 8GB of RAM here; having some Tomcat instances
co-existing with the database when there's that much room to work is not
that hard.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD