i had a quick search and couldnt really find any information on LQ, and the bits i found online werent incredibly helpful.

Anyhow, recently iv started doing a lot of work in Java (im currently coding an IM in Java) but im sure its a lot slower than the code i used to write in C++. I was not expecting my Java apps to run faster than my C++ apps (due to the VM) but i had been reading that Java programs can execute as slow as a third of the speed of a C++ program.

To me that seems very slow, and i was wondering how many performance issues Java programmers here have come across before. It does not appear to be a major problem, and i do enjoy coding in Java, however i wouldnt look forward to rewriting the entire system in C/C++ just to dramatically improve its performance

Im considering buying "Java Performance Tuning" for this reason, and im hoping with that the performance difference will be hardly noticeable

I think that's a bit exagerated. It's true that java is slower than C/C++, but my experience is that this only is a problem when creating java GUIs. All backend services (db querying and data processing) are just as quick as any other language. That is, if you write well-designed code.

I don't think an IM client is that time critical anyway. And if you let it running all the time eventually all the Java bytecode will be just-in-time compiled to native code by the VM JIT-compiler (assuming the VM has a JIT compiler).

But if you want to take 4 times longer to develop/debug your apps go with C...

iTux

Also, if you want your code to be maintainable, java (or an OO approach anyway) is definitely the way to go.