RE: Heisenberg and measurement intrusion....

Well, there is the concept of metaphor, and I rather like this one... :-)

Back in the 7.x days, measuring performance by turning on timed_statistics could have a very negative impact on the system. Thus, employing instrumentation could be metaphorically related to Heisenberg if the process of employing that instrumentation (thus observing or measuring) would in fact alter the database (the electron) such that your measurement was worthless.

I've seen "instrumentation" packages that people have written that have had a pretty negative impact on performance (I've seen products with traits like this too). Also, I've seen the nuclear approach (let's just monitor everything) to monitoring rather than the strategic approach (let's figure out where specific problem areas are and instrument them more fully) can cause performance problems.

Speaking of Metaphors...

That time of year thou mayst in me behold Where yellow leaves, or none, or few, do hang Upon those boughs which shake against the cold, Bare ruined choirs, where once the sweet birds sang. Shakespeare Sonnet LXXIII, a metaphor for me (either me getting older or loosing hair, I'm not sure which)... :-)

Cheers!!!

RF
Robert G. Freeman
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