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Subject: Re: Looking for help with computer problem.

Author: m.d.hurd

Date: 00:05:19 11/29/02

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On November 29, 2002 at 02:05:16, James T. Walker wrote:

>On November 28, 2002 at 19:27:19, Jeremiah Penery wrote:
>
>>On November 28, 2002 at 17:11:08, James T. Walker wrote:
>>
>>>On November 28, 2002 at 16:54:25, mike schoonover wrote:
>>>
>>>>could it be that the master drive determines the access speed?
>>>>or,the system gives the master priority,hoging resources?
>>>>regards
>>>>mike
>>>
>>>Hello Mike,
>>>The only problem with that theory is the computer where the TB's are on the
>>>"Master" drive is the slow one.  The fastest one uses the 8G/5400rpm as drive C
>>>(Master) and the 40G/7200rpm as drive D (Slave).  The chess programs are on the
>>>"C" drive in both cases.
>>>Jim
>>
>>I would guess that the reason for the slowdown is because the virtual memory
>>(pagefile) is on the same drive as the tablebases.  So, when it caches
>>information, it's copying on the same disk, while also trying to access other
>>tablebases.  On the other machine, it copies to a different disk, which will be
>>much faster.
>>
>>Other things that can affect the access speed of tablebases are disk
>>fragmentation and the physical position of the tablebase files on the disk.  If
>>the files are heavily fragmented on one system, and are contiguous on the other,
>>the fragmented ones should be quite a bit slower.  Files near the beginning of
>>the disk have faster access times and faster transfer rates than files near the
>>end of the disk, as well.
>
>Thanks for trying to help.  I did de-frag the drive on the slow computer and it
>seemed to help some.  It now starts out at almost the same speed but slowly lags
>behind.  For instance, both computers will reach 14 ply in 15 seconds on one
>computer and 16 seconds on the other.  But when getting to say 16 ply at 2:15 on
>one computer it takes like 3:10 on the other.   Also as you might guess, the NPS
>on the computers gets further apart with time.
>Jim

Hello Jim

One thing worth checking is the EGTB cache size, which is set in Options. Mine
was set at 1 mb. It might be worth experimenting with different sizes to see
what difference each size increase makes. The help file says to use a value of 1
to 8 mbs. However I seem to recall someone mentioned 16 mb was a good size to
use. I suppose the bigger the cache, up to the optimum figure, the less disk
access.

Regards

Mike.




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