[comp.sys.alliant] etime complex user time variance

xxrich@alliant1.lerc.nasa.gov (Rich Rinehart) (07/26/90)

Can anyone offer a good explaination as to why the user time
portion from etime can vary greatly (we just saw 2x difference)
between runs.  I can justify away some of it but not as much
as what we are seeing.  What are other peoples experiences?

-rich

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Rich Rinehart                  |     phone: 216-433-5211
NASA Lewis Research Center     |     email: xxrich@alliant1.lerc.nasa.gov
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dereks@aggie.sgi.com (Derek Spears) (07/28/90)

	Is your job locked into a CE? If not (as in the case of a program
compiled under pcc), the program could float onto IP's, which run much
slower. This random "floating about" to different type processors could
account for etime differences.

	Derek Spears
	dereks@aggie.sgi.com

xxrich@alliant1 (Rich Rinehart) (07/31/90)

In article <11052@odin.corp.sgi.com> dereks@aggie.sgi.com (Derek Spears) writes:
>
>	Is your job locked into a CE? If not (as in the case of a program
>compiled under pcc), the program could float onto IP's, which run much
>slower. This random "floating about" to different type processors could
>account for etime differences.

good point, but my question was regarding complex work (see subject).  I have
also noticed much variance (2x ?) in user time on individual ce's (FORTRAN jobs 
though, which will not run on the ip's).



--
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Rich Rinehart                  |     phone: 216-433-5211
NASA Lewis Research Center     |     email: xxrich@alliant1.lerc.nasa.gov
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