Hamsters 0.7.1 released

[Alessandro Scotti]

Hi all,
Hamsters 0.7.1 for Windows and Mac OS X is available here:

http://www.ascotti.org/programming/chess/hamsters.htm

(same zip for both operating systems).

This version fixes several bugs found in version 0.7 and should improve strength (a little) in both single and multiple thread modes.

[swami]

Thanks, Alessandro!

We need something to test to keep the hobby going!

[beachknight]

Agreed, Swami.

[Dr.Wael Deeb]

Unfortunately,it seems that this is a downgrade version of Hamsters this time
After playing around 20 games at long time controls facing various opponents,Hamsters 0.6 is performing much better than the newest version which is a MP engine....

[Dann Corbit]

Unfortunately,it seems that this is a downgrade version of Hamsters this time
After playing around 20 games at long time controls facing various opponents,Hamsters 0.6 is performing much better than the newest version which is a MP engine....

20 games is not enough to know unless it is absurdly lopsided.

[Alessandro Scotti]

Unfortunately,it seems that this is a downgrade version of Hamsters this time
After playing around 20 games at long time controls facing various opponents,Hamsters 0.6 is performing much better than the newest version which is a MP engine....

I have to say that it is very much possible that Hamsters in multiprocessor mode plays worse than with a single thread, because of bugs. I think Hamsters 0.7.1 has a better SMP than version 0.7, but I don't have neither the hardware to test nor enough time to perform code analysis and debugging. Right now, this is just the best I can offer. However, I'm pretty sure that without SMP version 0.6 is weaker than 0.7.1, by maybe 30-35 elo at my time control (1+1).

[Dr.Wael Deeb]

Unfortunately,it seems that this is a downgrade version of Hamsters this time
After playing around 20 games at long time controls facing various opponents,Hamsters 0.6 is performing much better than the newest version which is a MP engine....

I have to say that it is very much possible that Hamsters in multiprocessor mode plays worse than with a single thread, because of bugs. I think Hamsters 0.7.1 has a better SMP than version 0.7, but I don't have neither the hardware to test nor enough time to perform code analysis and debugging. Right now, this is just the best I can offer. However, I'm pretty sure that without SMP version 0.6 is weaker than 0.7.1, by maybe 30-35 elo at my time control (1+1).

If this is the case,I will repeat the testing of Hamsters 0.7.1 using it as a single playing chess engine and will report later when I have enough games....

[Dann Corbit]

Unfortunately,it seems that this is a downgrade version of Hamsters this time
After playing around 20 games at long time controls facing various opponents,Hamsters 0.6 is performing much better than the newest version which is a MP engine....

I have to say that it is very much possible that Hamsters in multiprocessor mode plays worse than with a single thread, because of bugs. I think Hamsters 0.7.1 has a better SMP than version 0.7, but I don't have neither the hardware to test nor enough time to perform code analysis and debugging. Right now, this is just the best I can offer. However, I'm pretty sure that without SMP version 0.6 is weaker than 0.7.1, by maybe 30-35 elo at my time control (1+1).

If this is the case,I will repeat the testing of Hamsters 0.7.1 using it as a single playing chess engine and will report later when I have enough games....

I ran Hamsters 0.6 verses Hamsters 0.7.1 with 4 threads and 0.7.1 won 30 to nothing.
c:\utils\pgn -X

Code: Select all

  # Name                                                   1                              2   Score   Buch  Sommb
-----------------------------------------------------------------------------------------------------------------
  1 Hamsters 0.7.1 64 bit     ****************************** 111111111111111111111111111111  30.0/30   0.0   0.00
  2 Hamsters 0.6              000000000000000000000000000000 ******************************   0.0/30 900.0   0.00

[Dann Corbit]

Hi all,
Hamsters 0.7.1 for Windows and Mac OS X is available here:

http://www.ascotti.org/programming/chess/hamsters.htm

(same zip for both operating systems).

This version fixes several bugs found in version 0.7 and should improve strength (a little) in both single and multiple thread modes.

On my SMP test, I noticed some interesting things.

Kiwi 0.7.1 with 4 threads outsearches 0.6 by a landslide (generally, it was three plies ahead in all of its searches.

The new version definitely understands pawns better.

Kiwi 0.7.1 seems to generate or count nodes in a Rybka-like fashion. With 4 threads, I was getting an NPS figure about 1/2 to 1/3 of single threaded 0.6 and yet 0.7.1 was pounding the stuffings out of 0.6 by outsearching. I see some possible explanations:
1. We are counting the nodes from only one thread
2. We are spending so much energy on figuring out which nodes to discard that we are searching "only the right" nodes.
3. Kiwi swallowed a little fish, and now uses Rybka nodes.
4. These new nodes are not little-bitty kiwi nodes, but actually belong to a Rhea or an Emu.

[Dann Corbit]

Here are the games, for those to whom 30:0 carnage is interesting:
http://cap.connx.com/chess-engines/new- ... rs.pgn.bz2

I plan to run a 1 verses 2 verses 3 verses 4 thread contest tonight.