Petr Baudis: <[email protected]>: >On Wed, May 25, 2011 at 10:41:14AM +0900, Hideki Kato wrote: >> Mark Boon: <[email protected]>: >> >But for MCTS it's not very efficient to simulate the same leaf many >> >times at once. So it will probably only be worth it if you can get in >> >a fairly large number of simulations at similar cost to one simulation >> >done by a CPU. >> >> That's not correct. Leaf parallelism is efficient enough and can >> compete root parallelism. > >Well, I'd argue root parallelism is not efficient enough either. ;-)
Either only reduces the variance; never expand the tree. We have to develop some better way. ;-) >> Past bad results are mainly due to synchronizing all simulations >> invoked from a leaf. > >Can you elaborate on an alternative to this? I thought that treating all >simulations invoked from a leaf as a single unit was the very point of >leaf parallelism. Just simply avoid synchronization. Tree-part updates the info in the search tree as soon as a result arrives, start descending tree, and send the leaf position to be simulated. # I used broadcasting (udp/ip) but point-to-point is also possible. For detail, see <http://www.geocities.jp/hideki_katoh/publications/gpw08-private.pdf>. Hideki -- Hideki Kato <mailto:[email protected]> _______________________________________________ Computer-go mailing list [email protected] http://dvandva.org/cgi-bin/mailman/listinfo/computer-go
