computer-go: Speed of PN-Search

[frank-steinmann@xxxxxxxxxxx (Frank Steinmann)]

Hi all,
I'm a computer go newbie, having the crazy idea to develop a good
go-program. :-)
I just implemented a Proof-Number-Search-algorithm to detect wether blocks
can build enough eyes to live or not. But I'm not happy with it yet. Despite
some optimizations, the number of nodes it can handle in one second,
searching a local 5x5-area, is about 1000. It seems a bit slowly to me,
'cause if there are only few stones in the area, I can't search deeper than
depth 3 in an acceptable time.

So my questions: How fast should/could the algorithm be? Are there any
tricks to speed it up? Which information should be stored in the nodes?

Thanks
Frank