But what I read, in-place upgrade has smaller outage, compared to dump/restore.
Correct, in fact if you do it with the link option, it will be very fast.
But so many articles on having bugs afterwards. Do you think it is a good idea to use pg_upgrade for critical database application?
It entirely depends, I have successfully used pg_upgrade many, many times. That is what -c is for, to work out all the kinks before you upgrade.
Or any other tool should I consider? For example - slony?
On at 2.5TB database, you very well be doing a lot more harm than good using a tool such as slony.
JD
-- Command Prompt, Inc. - http://www.commandprompt.com/ 503-667-4564 PostgreSQL Centered full stack support, consulting and development. Announcing "I'm offended" is basically telling the world you can't control your own emotions, so everyone else should do it for you.
