[darkxanthos]

Standard deviations assume normal distributions... but ultimately when you look for some two standard deviations from the mean, you're just look for an event that only occurs 95% of the time. A technique that works regardless of distribution is percentiles. Postgesql supports these now as well.

[sqldba]

I wish they went into more detail within the context of what we're discussing. I've looked at the wiki pages and my eyes glazed over.

Trying to pick out "bad" stats from the gigabytes of information I gather from the servers I manage is always a top-of-the-list thing that I want to do.

But when we're talking about 95%; well I mean it's fine for showing on a graph but how can you run alerting for something like that?