Yesterday we migrated many #postgresql databases to 16.2. It went smoothly for all of them except one.
The database is used by Sidekiq for 90% of the traffic. We choose a time window outside of working hours, but still we had some traffic, and we didn't turn off pods. The database was inaccessible for 10min. Jobs rescheduled, and quickly auto-scaling was triggered. I was not able to perform ANALYZE. So requests retrying at the same time + huge disk read. 💥
