Information on which 'version' of a chess engine to run?

[chessman2b]

Hi Folks:

I wanted to try out the Shashchess engine. When I downloaded the windows zip file it has a lot of versions in it. I'm running currently on an amd processor from about 6 years ago.

Any idea where I could find information on how to determine which version of an engine should be run on a particular computer?

Matthew

[Graham Banks]

Hi Folks:

I wanted to try out the Shashchess engine. When I downloaded the windows zip file it has a lot of versions in it. I'm running currently on an amd processor from about 6 years ago.

Any idea where I could find information on how to determine which version of an engine should be run on a particular computer?

Matthew

What are the details of your computer?

[abgursu]

If you don't want to test it yourself, try this order: bmi2, if not working avx2, if not working popcnt, and even it's not working 64.

But I recommend you to type bench in .exe files, compare the nodes/time values and pick the highest one. If a binary gives you error and doesn't start that one is probably not compitable with your pc, so pick another one.

Good day!

[lithander]

A tricky problem is when an engine uses an instruction like PEXT that on some CPUs is only implemented via microcode. So the executable won't crash because technically it's supported but it's going to run very slow.

For example in a ZEN2 CPU the PEXT instruction takes 250 clockcycles whereas in a ZEN3 CPU (and modern Intel CPUs) it's implemented in silicon and takes only one cycle to compute (with 3 cycles of latency).

This makes PEXT based slider generation the fastest option on ZEN3 and recent Intel but a terrible choice on a ZEN2 CPU.

[chessman2b]

Thanks for the info Folks. I can try a few and see what runs. On some of them it the .exe file says 86-64 which I take as meaning the engine is a 32 bit? There is one that says genera x64.

I'm hoping to get a new i7 in a month or two. Here are the current specs for the two machines I run my engines on:

Intel Xeon x5675 x2 sockets with 12 real cores (Numa) (24 virtual) base speed 3.06 GHz 48 GB Ram
(about 11 years old but still does well with chess engines)

Intel Xeon E3-1245 v5 3.5 GHz Quad Core 32 GB Ram (maybe 5 to 6 years old?)

Both Windows 10.