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Subject: Fritz's Tablebase Initialisation

Author: Mike Hood

Date: 04:47:57 05/05/04


I just let Filemon run while loading Fritz 8 to see why it takes so long. I was
shocked to see that during the initialisation Fritz tries to open every possible
tablebase. For instance...

Open kpk.nbw.emd -- good, it's there
Open kpknbw.emd -- file not found
Open kpk_nbw.emd -- file not found
Open kpk_nbw_emd -- file not found (I never knew this format was valid)
Open kpk.nbw -- file not found

And the same five accesses for the nbb file.

Why carry on with the other three after finding the first tablebase? But it gets
even wilder when it comes to the 6-piece tablebases. All 365 possible tablebase
pairs in all possible formats are accessed, even though I don't have any on my
disk. Thousands of "file not found" results. Just one example, to show how
ludicrous it is:

First Fritz tries to open krbnkp.nbw.emd, krbnkpnbw.emd, krbnkp_nbw.emd and
krbnkp.nbw.emd. Almost the same as before, except Fritz is assuming 6-piece
tablebases are compressed. But then Fritz tries to open krbnkp.0.nbw.emd,
krbnkp.0_nbw.emd, krbnkp.0nbw.emd and krbnkp.0_nbw_emd. Then krbnkp.1.nbw.emd,
etc... and krbnkp.2.nbw.emd... and all the way through to krbnkp.g.nbw.emd. That
means 136 disk accesses for a tablebase that I don't have! And that's only one
tablebase out of 365.

Wouldn't it be much easier just to scan the tablebase directory and only open
the files that actually exist?



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