Rybka 4 just around the corner it seems

[Alexander Schmidt]

Renting seems like a good solution to having the program hacked and rereleased for free as Ippolit. Very understandable decision by Vasik in order to safeguard his livelihood. And more evidence to users that pirating engines just will come back to hurt them in the long run.

Understandable, but still disappointing. The actions of a few have wrecked things for the rest of us.

Now Ippolit is guilty that people have to rent an engine? Fine, then Ippolit will help VR to get some extra money.

Rybka 4 will still be available for purchase as far as I understand...

[oreopoulos]

The problem is, you are leaving out a _lot_ of "middle-work". Where does that large set of independent positions come from? If you feed them to the program (say take 300 WAC positions and say "gimme the results for these" then I agree, it will be faster to search all to the same depth, independently. But if you are analyzing a _game_, how do you create those positions without first doing analysis to discover the interesting positions, and then analyzing those to discover more interesting positions, etc. That is not going to scale perfectly. It is going to scale poorly.

Ok. we first agree to the obvious. If the positions are different then we agree.

Now lets come to the situation of the same game.

Lets say we have a position, and take the first 4-best moves (and also suppose they are not highly transposive).
The task is the following.

"for every one of the 4 best moves, autoplay for 20 plies (depth 15)"
(autoplay with fixed depth ==15)

Now you could do it in 2 way.
a) One 4-core engine will get through its variation
b) 4x 1-core engines will get extend one move each.

Which is faster? The 1-core engines _DO_ get benefit of the hash along the prolongation.
On the other hand, when the MP-engine finishes the first task (autoplay first one of the 4-candidate moves) and comes to extend the second, the hash is worthless (i have never seen hash working more than 4-5 plies, )

[bob]

I have never seen so much disinformation from a single source. But once you notice the trend (bogus NPS, bogus total nodes, bogus PVs, bogus depth, bogus scores) then "bogus parallel search results" can't be too unexpected.

I think this was a misunderstanding?

I think Ray and Gian-Carlo are discussing IDeA, which is just an analyzing scheme in the Aquarium interface. It has nothing to do with the Rybka Cluster and is not programmed by Vasik Rajlich, as far as I know totally an independant project from Convekta. I don't know anything about IDeA I must admit, but it possibly takes advantage of the fact that if there is a cluster of positions that is related but is not directly in one move sequence, it pays off to analyze these crucial positions first before doing more minimaxing of the root position. You can skip an awful lot of nonessential variations if you have a good idea of the crucial positions already. This is just a very crude guess of what is going on, Gian-Carlo has looked at this I suppose and knows what he is talking about. Have not read the thread further. Sorry for interrupting the discussion

Regards, Eelco

I understood what was being discussed. But this all applies to multiple issues. The 4 cores could be 4 cluster nodes, or 4 cores on a single chip, or a combination. We have seen misleading reports about the efficiency of cluster Rybka, but _never_ any finite data (the cluster is for playing games, not running tests is the usual answer). Now we have yet another parallel issue that is most likely intentionally misleading in the way it is presented. I generally want to analyze a specific game. This kind of approach is not going to be any better than a normal parallel search, because there are dependencies involved. You can't evaluate things further into the tree until you have evaluated things that lead to those positions. Otherwise the answers are nowhere near as accurate.

The implication from what I saw was "this is more efficient than a normal parallel search, where everything else remains equal." There is no mention of "loss of quality" to gain the extra speed. And something definitely has to be lost, unless they have the perfect parallel algorithm. Which provably does not exist within the context of alpha/beta...

[Alexander Schmidt]

That should make some people happy.

Whom?

There are none so blind as those who will not see.

I had to google this one:

This idiom is used when people refuse to accept facts presented to them.

ROTFL Graham, you made my day.

The only fact you presented is "One told it's a clone". Got some more now?

I keep my eyes open and try to look at the facts. Did you see this one?

http://talkchess.com/forum/viewtopic.ph ... 39&t=30588

Did you look at it? Will you?

I am sure you won't

[oreopoulos]

The implication from what I saw was "this is more efficient than a normal parallel search, where everything else remains equal." There is no mention of "loss of quality" to gain the extra speed. And something definitely has to be lost, unless they have the perfect parallel algorithm. Which provably does not exist within the context of alpha/beta...

Personally i never implied that. Not even near that. for IDEA the engine is an evaluation function. The multiple instances of evaluators just speeds up the evaluation. The engine acts as a compass and it encapsulates search it self.

There is nothing near a perfect parallel algorithm. It is just hidden inside the engine. I mean when examining 2 positions in the tree, the engine certainly goes through positions is had previously examined, this is not saved.

If the engine was to build the tree, it is obvious that it would have done it much much faster. I really don't see a "problem"

[Graham Banks]

That should make some people happy.

Whom?

There are none so blind as those who will not see.

I had to google this one:

This idiom is used when people refuse to accept facts presented to them.

ROTFL Graham, you made my day.

The only fact you presented is "One told it's a clone". Got some more now?

I keep my eyes open and try to look at the facts. Did you see this one?

http://talkchess.com/forum/viewtopic.ph ... 39&t=30588

Did you look at it? Will you?

I am sure you won't

An old woman drops a $100 note in the street. This is seen by another person. The note blows into the path of somebody who did not see what had happened. This person pockets it, refusing to believe either the old woman or the witness. His excuse is that they can't prove it, so it is okay for him to claim it as his own.

[Michael Sherwin]

That should make some people happy.

Whom?

There are none so blind as those who will not see.

I had to google this one:

This idiom is used when people refuse to accept facts presented to them.

ROTFL Graham, you made my day.

The only fact you presented is "One told it's a clone". Got some more now?

I keep my eyes open and try to look at the facts. Did you see this one?

http://talkchess.com/forum/viewtopic.ph ... 39&t=30588

Did you look at it? Will you?

I am sure you won't

An old woman drops a $100 note in the street. This is seen by another person. The note blows into the path of somebody who did not see what had happened. This person pockets it, refusing to believe either the old woman or the witness. His excuse is that they can't prove it, so it is okay for him to claim it as his own.

A young prostitute drops a $100 note in the street. This is seen by her john. The note blows into the path of the john's wife who did not see what had happened. The wife pockets it, refusing to believe the young prostitute because her husband said that he dropped it. Her excuse is that her husband would not cheat on her, so it is okay for her to claim it as her own.

[Graham Banks]

A young prostitute drops a $100 note in the street. This is seen by her john. The note blows into the path of the john's wife who did not see what had happened. The wife pockets it, refusing to believe the young prostitute because her husband said that he dropped it. Her excuse is that her husband would not cheat on her, so it is okay for her to claim it as her own.

Very creative, young Johnny (oops I mean Mikey).

[Alexander Schmidt]

Did you look at it? Will you?

I am sure you won't

As I said Though it was meant sarcastic. He looked at it and saw that this little engineoutputs shake his happy little world. Instead he starts to telling me stories of old womans

An old woman drops a $100 note in the street. This is seen by another person. The note blows into the path of somebody who did not see what had happened. This person pockets it, refusing to believe either the old woman or the witness. His excuse is that they can't prove it, so it is okay for him to claim it as his own.

So VR is like an old women for you? Maybe he is the millionare who saw someone pick up $100 and now he is claiming it is his money? You give it to him. I would ask the bank of the old women, if she just picked up 100$ as she told and give it back to her.

Well if you want your lost purse back, you must say what is inside. If you can't you wont get it.
And if someone gives your purse out without asking what is inside, someone else will have taken your purse already.

[Michael Sherwin]

A young prostitute drops a $100 note in the street. This is seen by her john. The note blows into the path of the john's wife who did not see what had happened. The wife pockets it, refusing to believe the young prostitute because her husband said that he dropped it. Her excuse is that her husband would not cheat on her, so it is okay for her to claim it as her own.

Very creative, young Johnny (oops I mean Mikey).

I was only a john once and that was by accident!

I was already in love with her when she told me that I had to pay for it!

Oh and only my grandma was allowed to call me Mikey. Grandma!