Archive for August, 2006

Building chess tablebases over the Internet

Wednesday, August 23rd, 2006

I’ve read some stuff on the Internet about using pre-computed tablebases to solve complex endgames. Apparently you can load a five- or six- piece tablebase into a program like Fritz and it will then know how to mechanically solve any endgame with five (or six) pieces on the board.

I starting thinking about this, but more along the lines of building the tables dynamically, using a pool of cooperating computers on the Internet. The idea would be to direct your search towards certain game positions that you wanted to analyze. This would work well in static analysis and also in relatively slow correspondence time controls (like Gary Kasparov vs The World, or the upcoming The World vs Arno Nickel).

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Java Caches

Wednesday, August 23rd, 2006

I’ve been thinking for several years about the flaws in the Internet’s (nearly non-existant) caching model, and have reached several conclusions. First, caching policy is very difficult, basically impossible, to specify in some arbitrary protocol. This is one of the biggest problems we’ve got with caching – the cache manager has a lot of settings he can adjust, but the data provider has almost none – basically cache or don’t cache (oh yeah, he can specify a timeout, too). So, I’m led to conclude that data providers need a very flexible way to inform caches of their data’s caching policy, like a remote executable format, i.e. Java. My second conclusion is that what limited caching we’ve got is destroyed when people want to provide dynamic content. The only way I can see to cache dynamic content is to cache not the data, but the program used to create the data, and expect the client to run the program in order to display the data. And we don’t want to do that on the caches (if we can help it) for performance reasons. Again, a remote executable format, this time on the client, i.e. Java. My third major conclusion is that caching is a multicast operation and requires multicast support to be done, but that’s for a diferent paper. Thus, I’m proposing an integrated Java-based caching architecture using what I call “cachelets” on the caches to provide a flexible and usable caching architecture.

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