Extremely high "connection management call elapsed time"

I am wondering if anyone here ran into a situation where "connection management call elapsed time" timed statistic accounted for 83% of total DB time. We are also seeing long waits on "Library cache load lock" with very high rates of timeout on this wait (91% timeout).

This happens once every day or two, lasts two hours and then goes away on its own. It doesn't seem to coincide with our regular peak activity times or large reports, or backups or anything like this.

If you have suggestions on where I should look or what could be a possible cause for what I am seeing, I'd appreciate it a lot!

Chen

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