On 07/26/2012 03:48 PM, Gerhard Adam wrote:
I don't see anything that indicates resource consumption has increased,
therefore the number of service units can't increase [except through
calculation error]. Elapsed time also has to be accounted for by either
increased resource consumption or increased wait time. Since there is no
increase in resource consumption, then we have to conclude it is simply
increased waiting. Again, service units will no increase.
MSO is calculated using CPU service, so unless that goes up the numbers will no
change.
In the absence of a huge increase in the coefficients, it seems that it's
simply a reporting bug. The increased elapsed time is a different problem. I
would want to confirm that the reported service units matches a comparable
report from RMF.
Adam
Not true. Service units contribution from MSO involves a PRODUCT of
real memory usage and CPU usage. If memory usage goes up dramatically
and CPU usage stays constant or even declines slightly, with MSO > 0
this can significantly increase the service units. This can definitely
happen if you go from a real-memory constrained environment where
address spaces get all real pages that are not active trimmed from their
working set to one with an abundance of real memory where many pages
once referenced are retained in real memory even though no longer
referenced. MSO > 0 no longer makes sense when real memory is cheap and
plentiful relative to CP seconds and you want to encourage rather than
penalize practices and algorithms that use more real memory to reduce CP
usage.
But, less contention for real memory should, if anything, speed up job
execution, and the perception is that jobs are taking longer elapsed
time to run, not just using more SUs; so this seems an unlikely
explanation for what the site is observing.
--
Joel C. Ewing, Bentonville, AR [email protected]
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