Comment 73 for bug 574910

No-go. I just had it happen again! This time it was at 45 mins past the hour so nowhere near my snapshot time. System was so unresponsive that it kicked me off my ssh session. I tried a forced instance restart and once I did that I could suddenly log in again even though it didn't restart, was still pretty unresponsive though and I couldn't do anything meaningful on it. Eventually the restart happened but it didn't come back up properly so I just had to keep on trying to reconnect. I got back on again but it locked up again as I was remounting some EBV volumes. So another attempt at a restart... The problems all disappeared again almost 1 hour after it had begun.
It's frustrating trying to run a web service like this and having to come up with explanations for our customers when we disappear. And I have no idea where the blame lies for this! AWS? EBS? Lucid? Something else? Do I spend a day reverting back to Karmic? Do I throw away my reserved instance and set myself up in another availability zone or region?