Freecell Solver 1.5.1 (which is now available on the web) is now utilizing the
cache hash optimization. When using this optimization, hash elements that
were found to match a new element are moved to the beginning of their chains.
That way, they will be encountered more early by further states of this kind.
This optimization was inspired by Dr. Holroyd's description of the splay
tree, which is a binary tree optimized to be used as a cache.
At the moment, the cache hash option is on, at both the states and stacks
hashes. It can be turned off in either one or in both by modifiying the
source code. Having it as a run-time option should not be difficult at all.
In any case, I did not benchmark this optimization against normal hash
behaviour yet. It could make things slower, because it requires an extra
write to memory.
I'll let you know as soon as I have some timings.
Regards,
Shlomi Fish
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Shlomi Fish shlomif_at_techie.com
Home Page:
http://t2.technion.ac.il/~shlomif/
I don't believe in fairies. Oops! A fairy died.
I don't believe in fairies. Oops! Another fairy died.
Received on Mon Feb 26 2001 - 04:24:15 IST