Wait event bingo

How this for a random selection of wait events, some of these i never even heard of before

What seemed to have happened is that something had died and smon had decided to do parallel transaction recovery - this seemed to coinicide just around the time there was an out of space condition with the archive area which only last 60 seconds at most. The database returned to normal operation but not everything was working normally.

Smon seemed very confused and seemed to think that the arch area was still full

But the wait event shown about the smon session seemed to disagree with the graphic display

Anyway after looking at the screen for a while smon suddenly seemed to wake up and smell the coffee and everything kicked into life - at the same point this appeared in the alert log

2015-07-17 15:43:36.998000 +01:00
SMON: Parallel transaction recovery tried

Anyway - looks like there is some kind of bug here and smon wasn't waking up and realizing the issue. Sorted itself in the end with no intervention - strange one though.