Re: computer-go: unmake move?

[Don Dailey <drd@xxxxxxxxxxxxxxxxxxxxx>]

> Usually you are unmaking moves near the leafs, so the
> old position is still in the cache.  So memory bandwidth
> is not a problem.  Even if there is no cache, so copies
> go to memory, Pentium PCs should be able to copy over 100 MB/s.
> If the state is 1000 bytes, that limits performance to 100,000
> positions per second.

But how can that be?  I know I am getting about 300,000 per second and
my state size is almost 5000 bytes!   I'm not cheating either, I don't
count a node unless I do a state copy.

I will go over the code to see if there  is some error counting nodes,
but I am pretty sure I'm doing this correctly.

Don