Arasan 18.3

[jdart]

Arasan 18.3 is available from http://www.arasanchess.org.

Changes in Arasan 18.3:
1) Bug fix: properly handle "cores" and "memory" options for Winboard.
2) Adjust futility margins and allow futility pruning up to depth 5.
3) Modify pruning condiitions slightly.
4) Bug fix: guard against null move in updateHistoryMove.
5) Bug fix: fix locking for PV update.
6) Properly handle errors opening files in tuner program. Don't allow
validation (-V) when running multi-threaded (does not work). Some
code cleanup in the tuner.
7) Fix UCI tablebase type selection option.
8) Remove some restrictions on LMR.
9) Fix padding in NodeInfo for better alignment.
10) Allow reduction of moves in the killer and refutations phases of
movegen.
11) Bug fix: initialize child node from parent in searchSMP.

This is mostly a bug fix release. It is only marginally stronger than 18.2 (single-core) in my testing (about +8 ELO). However I expect the bug fixes will improve stability and may also increase performance especially when multi-threaded.

--Jon

[F.Huber]

Arasan 18.3 is available from http://www.arasanchess.org.

Thanks Jon!

Just for information:
The file 'arasanx-32.exe' in the Windows installer is in fact a 64bit program - only the file with the same name in the engine ZIP is indeed 32 bit!
(not the first time with such a problem in your releases ... )

Franz

[jdart]

The file 'arasanx-32.exe' in the Windows installer is in fact a 64bit program - only the file with the same name in the engine ZIP is indeed 32 bit!

Should be fixed now.

--Jon

[Sylwy]

http://talkchess.com/forum/viewtopic.ph ... 30&t=50060

[jdart]

The engine does not impose a hard limit on either hash size or tablebase cache size.

But the operating system may impose a limit. See https://msdn.microsoft.com/en-us/librar ... s.85).aspx for Windows limits.

Also I do not recommend using more than 1/2 of the physical memory size for the hash table.

The Arasan GUI uses the 32-bit version of the engine and the UI will only let you set 1.5G for hash size.

--Jon

[Graham Banks]

I have a request Graham. Be as you know how to check for correct work table bases Arasan program Chess GUI.

Only by watching games and Jon has probably kept an eye on more Arasan games than I have.