Why I won't Buy Rybka 5

[kingliveson]

Here are some quick benchmarks for Critter 1.4 Linux/Native and Windows/Wine:
<snip>

Thanks for benchmarking. I know it sounds like heresy, but 1.4 had never seen any Linux on my computer. It was compiled/tested with VirtualBox on a Win64 host, so I had no idea what about its performance in native Linux. However, 1.2 was compiled/tested with genuine Linux and was indeed a bit slower than the Windows build on the same computer.

Critter is quite dependent on the compiler to be able to do link-time inlining, but I never managed to harness any gain from -lto with gcc

It is interesting however that Bob is advocating I buy Rybka 5.

If R5 does not run on Linux it is already obsolete

Rybka is falling behind and will fall further with no Linux version. If I gather correctly, your preferred environment is not GNU/Linux. Even then, you ported necessary portion of the code in no time. Conversion to pthread is really the biggest deal in my view. And this brings me to the next point regarding GCC/PGO. Profile Guided Optimization is currently broken for threaded apps. Intel® Parallel Studio XE 2011 for Linux is free for non-commercial use. Critter 1.4 is the strongest chess program on Linux today, so am not sure how much more ICC can help.

I think the older version might produce faster binary.

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parallel_studio_xe_2011_sp1_update1.tgz
parallel_studio_xe_2011_update1.tgz

[hyatt]

Here are some quick benchmarks for Critter 1.4 Linux/Native and Windows/Wine:

Native

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time: 59986 nodes: 335399440 evals: 252662019 knps: 5591
phash: 80.79% evalcache: 10.78% lazy: 38.04% eg_recog: 0
splits: 28627

Wine

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time: 59986 nodes: 309578917 evals: 233593356 knps: 5160
phash: 81.29% evalcache: 10.49% lazy: 37.74% eg_recog: 0
splits: 25870

Native

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time: 99986 nodes: 559984269 evals: 413473219 knps: 5600
phash: 80.95% evalcache: 11.49% lazy: 37.44% eg_recog: 2
splits: 50156

Wine

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time: 99986 nodes: 518032761 evals: 380642623 knps: 5181
phash: 80.75% evalcache: 11.45% lazy: 36.83% eg_recog: 0
splits: 43407

Native

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time: 199986 nodes: 1154964601 evals: 852760483 knps: 5775
phash: 81.35% evalcache: 11.33% lazy: 39.14% eg_recog: 2
splits: 66990

Wine

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time: 199986 nodes: 1064932281 evals: 790297153 knps: 5325
phash: 82.23% evalcache: 11.35% lazy: 38.83% eg_recog: 1
splits: 75969

As you can see, native is outperforming wine by ~8.5%. This is from bare-naked runs. Now when you include overhead produced by wine+GUI, it is really not worth it. These results are actually good compared to others that I've seen, and the slow-down is definitively not "urban legend," but real.

It is interesting however that Bob is advocating I buy Rybka 5.

More info needed. Are these run on a 64 bit cpu? With a 64 bit version of linux? with a 64 bit version of wine?

I NEVER see any slow-down until I get to graphics-intensive stuff. I would not voluntarily run something like windows doom under wine, for example, although it is not THAT slow.

[kingliveson]

More info needed. Are these run on a 64 bit cpu? With a 64 bit version of linux? with a 64 bit version of wine?

Yes. I've seen as much as ~25% reduction. The results are not surprising when you have a translation layer.