schack wrote:Larry - without giving away trade secrets, how did you get the faster compile? More broadly, what compiler are you using?
I got some hints from some of the other engine compilers. One is simple, but I promised not to tell ( often helps about 1.2 of 1 percent!). Moslty you just try things to see what helps. We have to take a kind of middle ground in what we target since we have to support a wide range of CPUs. I try to aim for good speed on an intel i7 4 core CPU. In earlier versions of Komodo, I had to stop using -O3 in mingw/gcc since it messed up some things. But it seems fine once again. I experimented with how long to run bench test searches for pgo builds. You can also selectively turn on or off various kinds of optimizations. No magic. I just tried a lot of things. I also compared compiled results with various compiler versions and now stick with the one that seems to make Komodo the fastest.
Whatever you try seems to help on some CPUs and hurt on others. Probably my time is best spent making the code faster than trying to outguess the compiler. Trying to make an assembly version would probably make my head explode.
Does the version of gcc matter? I did a quick test using six different versions and couldn't find any significant (>1-1.2%) differences, but then, it wasn't really a serious test.
schack wrote:Does the version of gcc matter? I did a quick test using six different versions and couldn't find any significant (>1-1.2%) differences, but then, it wasn't really a serious test.
It made a difference for Komodo. Komodo does a lot of things differently than other programs, so maybe that is why. I have not tried the latest gcc, and probably should.
lkaufman wrote:Komodo 11.01 is being released today at komodochess.com. It was made available yesterday to subscribers, but those who dowloaded it should download it again now because we made a slightly faster compile and because the readme file was not ready yesterday. Pricing is the same as for Komodo 10, which should go on sale shortly with Komodo 9.02 becoming the free version.
I think it's great that team Komodo makes these older versions available for free. It's a generous policy.
I'm still waiting for Robert Houdart to release Houdini 2 as a free download, since I never bought that particular engine. I'm guessing he hasn't because Houdini 2 is still sold with one of the Chess King packages.
lkaufman wrote:
We estimate that Komodo 11.01 is about five elo stronger than Komodo 11, about ten elo stronger than our last release Komodo 10.4
Just to be completely clear, is the estimate of Komodo 11.01 vs Komodo 10.4 +10 Elo and not +15 Elo ? I'm still amazed that you guys keep eking more Elo out of an already hugely strong engine.
Komodo is like an elo-drenched mushroom, waiting to be squeezed.
Same goes true for SF.
Quite probably, the amount of squeezable elo is larger than the elo already in.
Many work with my own project and not follow the Komodo news the last days. But for minutes I made a subscription for one year and I am sure tomorrow I have a great Komodo day.
Thanks Larry and Mark and good luck with the new version 11.01.
