How to optimize for dual, quad and higher multi-processors?

Question

Folks, I've been programming high speed software over 20 years and know virtually every trick in the book from micro-bench making cooperative, profiling, user-mode multitasking, tail recursion, you name it for very high performance stuff on Linux, Windows, and more.

The problem is that I find myself befuddled by what happens when multiple threads of CPU intensive work are exposed to a multi-core processors.

The results from performance in micro benchmarks of various ways of sharing date between threads (on different cores) don't seem to follow logic.

It's clear that there is some "hidden interaction" between the cores which isn't obvious from my own programming code. I hear of L1 cache and other issues but those are opaque to me.

Question is: Where can I learn this stuff ? I am looking for an in depth book on how multi-core processors work, how to program to capitalize on their memory caches or other hardware architecture instead of being punished by them.

Any advice or great websites or books? After much Googling, I'm coming up empty.

Sincerely, Wayne

Answer 1

This book taught me a lot about these sorts of issues about why raw CPU power is not necessary the only thing to pay attention to. I used it in grad school years ago, but I think all of the principles still apply:

http://www.amazon.com/Computer-Architecture-Quantitative-Approach-4th/dp/0123704901

And essentially a major issue in multi-process configurations is synchronizing the access to the main memory, if you don't do this right it can be a real bottleneck in the performance. It's pretty complex with the caches that have to be kept in sync.