Re: [Bug-gnubg] MD5 gnubg_ts.bd

[Joern Thyssen]

On Fri, Dec 27, 2002 at 11:52:54AM +0100, Morten Wang wrote
> * Joern Thyssen
> > I haven't managed to generate the 10x6 database yet. I don't think the
> > program is efficient enough. Back to the drawing board... ;-)
> 
> I tried to generate it today, but felt that I should kill makebearoff
> when it had eaten 700M of RAM.  What hash-size should I use, 275M
> seems a bit too large?

The hash used in makebearoff is not very optimal. It uses

used memory = number of entries * ( 6 bytes + sizeof ( bearoff data ) )

For example, the two sided bearoff database has 8 bytes of data, so the
hash uses number of entries * 14 bytes. The number of entries is
calculated as the amount of cache given with the -S argument divided by
8 bytes (confused?).

So if you specify a cache size of 275M, it'll actually use 476M of
memory as the overhead is quite dramatic... It's on my TODO list to fix
this.

If some of the computer scientists out there has some very good ideas
about how to cache previously calculated bearoff equities efficient in
memory, please let me know!

Jørn