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Archives of the TeradataForum
Message Posted: Wed, 25 Jan 2012 @ 14:57:32 GMT
Subj: | | Re: Performance Metrics: What explains this kind of observation? |
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From: | | Anderson, Dirk |
Might want to check for IO or CPU skewing.
Time is certainly one consideration in perf tuning. If the difference in run time is significant, we tend to favor the faster running query,
even if it uses more resources, because it's in/out faster. We don't have any particular criteria to make that decision, it's just a judgment call
on a case-by-case basis, taking into consideration all the performance metrics.
For curiosity, you might trying running the 2 queries on a busy system....it might be interesting to see if the one demanding greater cpu/io
resources (Q2) takes proportionally longer to run when the system is heavily taxed.
Thanks.
Dirk Anderson
SVP, Manager of Architecture & Strategy
Chief Data Officer Organization
Bank of America
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