Re: [Bug-gnubg] Multi-threaded cubeful #Q0 bug

[Christian Anthon]

Jonathan Kinsey wrote:
> I'm pretty sure this is a bug in the cache code that doesn't treat the
> cubeful
> equities correctly. I'm in the midst of changing the cache code so
> can't check
> in a fix at the moment. The fact that is seems to work on some machines is
> probably a mixture of the default values being copied (0 vs rubbish)
> and the
> amount of cache usage (number of threads).
>
If that is the case turning of the cache should cure the problem. I
believe that you can do "set cache 0" in the command panel to turn off
the cache. Could somebody who observe the problem try that, please.
> I think the fix is to set the cubeful equity to zero when adding it to
> the cache
> (or maybe copy it if this is calculated?). The fix might be just adding:
> ec.ar[ OUTPUT_CUBEFUL_EQUITY ] = 0;
> before the CacheAdd calls (or in the CacheAdd function). It looks like
> the 6th
> value isn't set either (equity?) so this might need fixing as well?
>
I don't know too much about how the cache works. However, plied cubeful
evaluation are not a function of the win/g/bg probabilities alone. So I
think that both the cubeful and cubeless equties (the 6'th value) should
be right.

The 6'th value is the cubeless equity.

I wonder how often we actually hit a plied evaluation, most of the time
I guess that it is the 0ply ones that we hit, but perhaps I'm wrong. I
haven't really looked at the code...

Christian.