Would there be any reason to do a tournament with a fixed search depth and unlimited time? My thought is that a fixed depth rating list would indicate more accurate evaluation functions. The problem is that sometimes speed compensates for accuracy and those two things work in concert. Anyone else ...

speed-up vs. core count depends heavily on the algorithm and implementation. These days, the engines that scale the best use some form of DTS (Dynamic Tree Splitting). I'll throw in a shameless 'Thanks!' to Dr. Hyatt here. See below:

http://www.cis.uab.edu/hyatt/search.html ...

A couple of comments on this:

1. The most advanced engines have the ability to utilize 8 cores (8 threads), however there are marginal ELO gains going from 4 to 8 cores. Beyond 8 cores some programs actually perform at a lower level, due to overhead and thread-induced inefficiencies. From this ...

Has anyone performed tests to find the optimal hash size for Stockfish to play standard time controls?

If not, I will perform the tests myself, but I didn't want to 'waste' a bunch of CPU time if someone has already gone through the rigors.

-James

Bob, I know you don't fulfill requests like this, but could you please have a couple of your grad students produce a 'new' engine using 'snippets of code' from the strongest engines? I'd like to see the ELO you guys could get...could be impressive I'd think.

-James

When testing an engine, is it best to test/tune new versions against old versions or is it better to test/tune against a variety of engines (which may include older versions of the engine being tested)?

It seems to me that testing and tuning for the purpose of increasing ELO should involve a ...

I'm running Ubuntu 10.04 LTS 64-bit, running Stockfish 1.7.1 JA with xboard and polyglot on an AMD Phenom x4 (quad core cpu). I've specified 4 threads in the ini file that polyglot uses, but Stockfish does not use 4 cores. All other behavior is normal, logs on to FICS, uses the book, wins a lot, etc ...