Re: FSM corruption leading to errors

On 10/20/16 10:15 PM, Michael Paquier wrote:
> 2) If anything is found, stop the server and delete the files manually.
> 3) Re-start the server.
> OK, that's troublesome and costly for large relations, but we know
> that's the safest way to go for any versions, and there is no need to
> complicate the code with any one-time repairing extensions.

Wouldn't you need to run around to all your replicas and do that as well?

> Speaking of which, I implemented a small extension able to truncate
> the FSM up to the size of the relation as attached, but as I looked at
> it SMGR_TRUNCATE_FSM has been introduced in 9.6 so its range of action
> is rather limited... And I pushed as well a version on github:
> https://github.com/michaelpq/pg_plugins/tree/master/pg_fix_truncation
> The limitation range of such an extension is a argument good enough to
> just rely on the stop/delete-FSM/start method to fix an instance and
> let VACUUM do the rest of the work. That looks to work but use it at
> your own risk.

Shouldn't the truncation be logged before it's performed?
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