(none)

MCCALPIN at SCRI1.SCRI.FSU.EDU MCCALPIN at SCRI1.SCRI.FSU.EDU
Sat May 6 08:29:01 AEST 1989


We have a Power Series 120 machine here for a demo/loan, and
I have had trouble getting anything useful out of the Power
Fortran preprocessor.  The code is basically a whole bunch of double
DO loops, with an iteration count of about 40 on the outer loop and
100 on the inner loops.

I ran the code with the following command:
	f77 -O2 test.f -o test
	time test
and it took 16.3 seconds

I re-ran it with: f77 -pfa keep -O2 test.f -o test
and it took 26.4 seconds!

I ran it again with: f77 -pfa keep -WK,-O=4,-UR=4 -O2 test.f -o test
and it got back down to 16.2 seconds.

This code seems ideal for loop-splitting parallelization, and the
intermediate code files show DOACROSS directives on all the important
loops.

Anybody have any ideas of something I might be doing wrong?

John D. McCalpin
mccalpin at masig1.ocean.fsu.edu		mccalpin at nu.cs.fsu.edu
mccalpin at fsu (BITNET or MFENET)



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