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We have just released Komodo 10.4 at komodochess.com. It is about 20 elo stronger than Komodo 10.3 (at blitz levels) and has one new UCI option, "variety". Improvements were in both search and eval. Linux users will see an even larger elo gain. In my testing it leads by 13 elo against Houdini 5.01 at 2' + 1" after 1350 games on four threads. This will probably be the last of the 10.x series. As usual, it is free for subscribers and available for a 20% discount for buyers of Komodo 9 or later version.

It would be nice to see it beat Houdini in rating list.
How does it go against Stockfish ?

JJJ wrote:It would be nice to see it beat Houdini in rating list.
How does it go against Stockfish ?

As usual, recent Stockfish will still beat Komodo in direct blitz matches, but I am optimistic that Komodo 10.4 will top the CCRL 40/40 rating list and perhaps some others. I think there is some time limit and core count at which Komodo would win a match from Stockfish, but it is not practical for us to determine what those numbers are. If TCEC resumes, perhaps we'll find out.

I feel optimist for you to catch Stockfish anytime soon. Congrats for your last update and great work.

Larry - have you had access to a Ryzen setup to test?

schack wrote:Larry - have you had access to a Ryzen setup to test?

No.

lkaufman wrote:We have just released Komodo 10.4 at komodochess.com. It is about 20 elo stronger than Komodo 10.3 (at blitz levels) and has one new UCI option, "variety". Improvements were in both search and eval. Linux users will see an even larger elo gain. In my testing it leads by 13 elo against Houdini 5.01 at 2' + 1" after 1350 games on four threads. This will probably be the last of the 10.x series. As usual, it is free for subscribers and available for a 20% discount for buyers of Komodo 9 or later version.

Thanks Mark and Larry! Good work. May I ask what variety is about?

Sincerely,

Tim.

Sure.

"Variety" modifies something in the evaluation function. A user can enter a number from 0 (no variety--always play the best move) to 20 (most variety, play more different moves). The value of "Variety" defines the magnitude of this evaluation change. At the start of each new game, Komodo randomly selects a value in the range of 0...Value, and modifies this evaluation term. For the rest of the game it uses this new value in computing the evaluation. These smallish changes are enough to have Komodo play a variety of different games, without it changing elo much.

This means a human play will get some different move choices (not one forced moves but in places where several moves have a close eval). It is possible it is even useful in computer match play, since games will vary instead of Komodo always choosing the same move.

We were surprised to find that even the higher Variety settings do not hurt elo by much. In fact, some test matches did a little better than default. But for best play Variety=0 is probably best.

One last use: prevent someone with a copy of Komodo from "booking up" against your Komodo.

Mark

schack wrote:Larry - have you had access to a Ryzen setup to test?

According to an article on ChessBase site, quoting tests from a French source, Komodo benefits considerably more than Stockfish from Ryzen (compared to the most similar Intel processor). Based on that article, Ryzen is clearly the better buy for chess, especially for Komodo, but I don't have any personal knowledge of it yet. Perhaps our next hardware purchase will be Ryzen. But we don't have much use for just an 8 core machine, when we already have 80 cores between us testing regularly. If one of our five main machines goes bad, Ryzen might be the replacement.

Preliminary results I got are:
About 12.000 kN/s in start position with a Ryzen 1800X (HT)
versus 9.5000 kN/s with a 5960X Intel 8-core desktop (no-HT)

Maybe comparing apples and oranges to you but hey, we all know Intel's HT sucks, right ? At least I diabled it as long as I can remember.

P.S. Neither setup was OC-ed.