On Mon, Sep 29, 2008 at 8:28 AM, <glassfish_at_javadesktop.org> wrote:
>>where using only a single cluster instance per physical machine would waste resources
> Why? Just because of garbage collection? Or is one instance (or JVM) restricted or why isn't it possible that one instance take all the resources of a big machine (e.g. 16 GB ram, 8 cores)?
Depends also on the OS. If you're on something like 64-bit Solaris
then 1 process can work with that much memory
without too much trouble.
Other OSes may limit how much memory a process (and even the OS) can
see, the maximum number of file descriptors
per process, etc.
> Such an instance is not restricted to a maximum of threads, isn't it?
> So why should I use two instances and not letting do one instance the double work?
> It would be nice if someone can help me to find arguments, why it's advisable to have 2 (or more) instances on big servers or is the garbage collection the only reason (and another one that it takes longer for garbahe collection to clean up big ammounts of memory)?.
I'd also be keen to hear other peoples rules of thumb on this.
--
Rasputnik :: Jack of All Trades - Master of Nuns
http://number9.hellooperator.net/