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Subject: Re: smp question about kns, engine, and other program tasks-Mr Hyatt

Author: Slater Wold

Date: 03:54:42 12/01/01

Go up one level in this thread


On November 30, 2001 at 23:32:40, Robert Hyatt wrote:

>On November 30, 2001 at 12:18:20, Slater Wold wrote:
>
>>On November 30, 2001 at 11:59:01, Robert Hyatt wrote:
>>
>>>On November 30, 2001 at 02:31:18, Slater Wold wrote:
>>>
>>>>On November 29, 2001 at 21:21:33, K. Burcham wrote:
>>>>
>>>>>
>>>>>
>>>>>Mr Hyatt. i have read the posts here about deep fritz and its kns increase with
>>>>>two processors.
>>>>>
>>>>>from the info i have seen with my dual machine, i have become curious about
>>>>>something. below are the examples with difference in hardware.
>>>>>
>>>>>program A on single processor 1500 mhz     1400 kns
>>>>>program A on dual   processor 3000 mhz     2000 kns
>>>>>
>>>>>program B on single processor 1500 mhz     1400 kns
>>>>>program B on dual   processor 3000 mhz     1400 to 1500 kns
>>>>>
>>>>>
>>>>>my question is only about the chess software. not the hardware. not the ram.
>>>>>not the hash.
>>>>>
>>>>>is it possible with these smp programs that something else going on in the chess
>>>>>software, that you can comment on. in other words if this kns is accurate and a
>>>>>true value (that deep fritz is giving us), then is it possible the program is
>>>>>doing something else with this second processor that will not show a kns
>>>>>increase but will add to its strength. the reason for this question is that when
>>>>>i run task manager in windows 2000, it shows that the program is using the
>>>>>second processor with deep fritz as much as my other smp programs (90 to 100%)
>>>>>but it shows no increase in kns.
>>>>>
>>>>>kburcham
>>>>
>>>>No.  Because it's not solving the problem any quicker either.
>>>
>>>
>>>For the record, if you run crafty, you will _always_ see both cpus running
>>>at 100%.  But it is possible that one thread is in a spin-lock waiting on
>>>the other to release something, or that one is spinning waiting on work.
>>>
>>>IE just because a cpu is busy doesn't mean it is busy doing something
>>>_useful_.  :)
>>
>>Speaking of which, did you know Crafty reports the wrong CPU usage time in
>>Windows?  It always says that I am using like 90% when task manager (along with
>>other utilities) say it's using 100%.
>>
>
>I have seen this, but since I don't run windows here, I have never been able
>to track it down.  If you are interested, I can tell you how the timing stuff
>works and perhaps get it right...

Sure.  Send me an e-mail.  I'd do whatever I can.

>
>
>
>
>>I also checked the memory paging in Crafty between 3xxMB ram and 7xxMB RAM.  I
>>am guessing Crafty does the global lock, because it did extremly well.  Better
>>than any others tested.
>
>
>Not sure what you mean by "global lock"...

Locking the memory.  I've seen a lot of SMP programs swap over a MB a sec
because the memory is not being locked.  Almost a must in Windows 2000.

Anyone who's interested, can run an SMP program on a Windows 2000 machine, and
press ALT+TAB to go to another running program.  See how much memory Windows
2000 swaps in order to do this.  At times it can be > 3MB/sec.  perfmon will
report this.



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