[Other] A quick comparison v0.21b vs v0.22b

I finally finished with the new move and transposition table representation along with a number of other optimizations. I will put the new version up for download tonight.

I am still not sure what the optimal size for the transposition tables is, and it can not be changed by the interface yet. I will leave this for a later version though.

A quick comparison

I made a simple comparison to see how much speed Mediocre has gained from these changes. By simply letting the both versions calculate the starting position for 9 plies we get a decent idea of the differences, note however that the new Mediocre can use a larger transposition table and will probably be even faster further into the game.

Mediocre v0.21b

Ply Eval   Time   Nodes Line
1   20      109      21 Nc3 
2    0      140     107 Nc3 Nc6 
3   20      156     223 Nc3 Nc6 Nf3 
4    0      203     728 Nc3 Nc6 Nf3 Nf6 
5    7      281    2066 Nc3 Nc6 Nf3 Nf6 d4 
6    0      625    5940 Nc3 Nc6 Nf3 Nf6 d4  d5 
7   15     1922   25719 Nc3 Nc6 Nf3 Nf6 d4  d5  Be3 
8    0     7015   81963 Nc3 Nc6 Nf3 Nf6 d4  d5  Be3 Be6 
9   19   136609 1085895 e4  Nf6 e5  Nd5 Nf3 Nc6 Bc4 Nb6 Na3

Total time: 2:16.609

Mediocre v0.22b

Ply Eval Time   Nodes Line
1   20     47      21 Nc3 
2    0     79     107 Nc3 Nc6 
3   20     79     223 Nc3 Nc6 Nf3 
4    0     94     728 Nc3 Nc6 Nf3 Nf6 
5    7    125    2066 Nc3 Nc6 Nf3 Nf6 d4 
6    0    172    5940 Nc3 Nc6 Nf3 Nf6 d4  d5 
7   15    329   25406 Nc3 Nc6 Nf3 Nf6 d4  d5  Be3 
8    0    938   79321 Nc3 Nc6 Nf3 Nf6 d4  d5  Be3 Be6 
9   19  19235 1176165 e4  Nf6 e5  Nd5 Nf3 Nc6 Bc4 Nb6 Na3 
Total time: 19.250

The new version is almost 2 minutes faster to 9 ply. A remarkable difference really.

Notice how the number of nodes differ slightly, this evens out over time though, and the changes I made to hash and killer move values makes the new version visit less moves later in the game.

The expected lines are exactly the same though, so we know I did not mess up anything when implementing this.

The important thing is the nodes per second here though. Clearly Mediocre has improved tremendously in that area. :)

Looking ahead

I think it is time we start working on the evaluation now. What is the use to search deep if you do not know what you are searching for? :)

Also a few extensions, like check and singular response extension, would be nice.

Further on I will start working with the repetition detection again, we should be able to gain some speed there as well from cutting off drawn repetition lines.