References for threading and multi-core cpus

[Stephen Upton]

Hi all,

I'm looking for any good reference material on programming in java on multi-core machines. I'm looking for ways to query the number of cores on a machine, so that I may then tailor the number of threads I generate or alternatively, just starting different jvm's, since the threads/jvm will be independent jobs. Any hints on best practice on this would be welcome as well.

thanks!
steve

[Henry Wong]

I'm looking for ways to query the number of cores on a machine, so that I may then tailor the number of threads ....

Take a look at the availableProcessors() method of the Runtime class.

Henry

[Stephen Upton]

Thanks Henry! That helps on the second part. I have your book on Java Threads, which helps with the first part. I'm now curious as to best practices or ideas on figuring out whether it's best just to start a new jvm or start a thread for my compute task (the one I'm using the jvm or thread for).

thanks!
steve

[Bill Shirley]

I would say there's no reason not to spawn a new thread (regardless of the executing architecture) as long as the count stays under something reasonable.

(Your definition of reasonable may vary from the next guy's)