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Subject: log files are now available

Author: Robert Hyatt

Date: 08:09:32 09/06/02

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I just created a new sub-directory on the ftp machine..

ftp.cis.uab.edu/pub/hyatt/smpdata

There is a read.me that explains what the files are.  I have uploaded the
1cpu log, the four 2cpu logs, the raw data file I created, and the program
that will take that raw data and compute the speedups and print them in a
readable fashion.

If I made any errors in going from the logs to my raw data file, please post
the "correction" here and I'll update the table and post it again...  I found
a couple of errors last night between posting the three 2cpu table and posting
the four 2cpu table.  I corrected the errors.  But that doesn't mean there are
not others.  I am going to re-check myself as well, but you can draw any
conclusions you want from the logs.

They might convince you that SMP can turn your hair grey at times. :)

For more fun look at the data I posted for Martin _first_.  One position ran
_slower_ with two cpus than with one, once, and got zero speedup in another
case, and also had two that were just over 2.0...  wildly varying...

The couple of 2cpu positions that produce > 2.0 speedups every run need some
attention.  That indicates that for some reason, my move ordering is simply
going badly wrong.  But since it is repeatable, it ought to be findable as
well.  Whether it is actually "fixable" is unknown, because a deeper search
_should_ reveal things about a position you didn't know after completing a
shallower search, and all the move ordering "tricks" might be loaded with
biased data that is suddenly horribly wrong...

Also the positions that consistently produce speedups of less than 1.25 or so
also need equal attention as those are even more problematic, since a lot of
work is being done without much return.

The position with a negative speedup (slowdown) is going to get a lot of
attention from me (the position kopec 2 that I first posted for Martin last
night).  :)



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