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Subject: Re: Mate in 19 - Glaurung Seems Faster

Author: Tord Romstad

Date: 09:46:53 12/01/05

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On December 01, 2005 at 10:42:00, Steve Maughan wrote:

>Centrino 2 GHz
>
>[D]3n3k/bp3pp1/8/8/R1Q2R2/6p1/B2p1PP1/q1rn2K1 w - -
>
>Engine: Glaurung Mainz (128 MB)
>by Tord Romstad
>
>10/45  0:11   0.00     1.Rh4+ Kg8 2.Rh8+ Kxh8 3.Qh4+ Kg8
>                       4.Qxd8+ Kh7 5.Rh4+ Kg6 6.Qd6+ Qf6
>                       7.Qxg3+ Qg5 8.Qd6+ Qf6 9.Qg3+ Qg5 (4.858.674) 431
>
>11/47  0:21   +M19     1.Rh4+ Kg8 2.Rh8+ Kxh8 3.Qh4+ Kg8
>                       4.Qxd8+ Kh7 5.Rh4+ Kg6 6.Qd3+ f5
>                       7.Qxg3+ Kf6 8.Qd6+ Kg5 9.Rh5+ Kxh5
>                       10.Bf7+ Kg5 11.Qg3+ Kf6 12.Qg6+ Ke5
>                       13.Qe6+ Kf4 14.g3+ (9.646.864) 453

Hi Steve,

The PV is incomplete, which makes me a bit worried.  Glaurung should never
announce
mate unless the PV ends in a mate.  Do you use a GUI or some other tool which
truncate
the PVs?  Otherwise, I have a new bug to track down.  :-(

The current development version of Glaurung is much faster in this position, by
the way.
On my iMac G5 (which is about half as fast as your Centrino), it announces mate
in 21
after 6 seconds and 8 plies, and reduces this to mate in 19 at the next
iteration after 11
seconds.  The reason for the improved solution time is simple:  I am
experimenting with
unlimited checks in the qsearch (Glaurung Mainz searches checks only in the
first 3 plies
of the qsearch).

Tord





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