Re: Offline enabling/disabling of data checksums - Mailing list pgsql-hackers

From Michael Banck
Subject Re: Offline enabling/disabling of data checksums
Date
Msg-id 1552577180.9697.4.camel@credativ.de
Whole thread Raw
In response to Re: Offline enabling/disabling of data checksums  (Magnus Hagander <magnus@hagander.net>)
Responses Re: Offline enabling/disabling of data checksums
Re: Offline enabling/disabling of data checksums
List pgsql-hackers
Hi,

Am Donnerstag, den 14.03.2019, 15:26 +0100 schrieb Magnus Hagander:
> Given that the failure is data corruption, I don't think big fat
> warning is enough. We should really make it impossible to start up the
> postmaster by mistake during the checksum generation. People don't
> read the documentation until it's too late. And it might not even be
> under their control - some automated tool might go in and try to start
> postgres, and boom, corruption.

I guess you're right.

> One big-hammer method could be similar to what pg_upgrade does --
> temporarily rename away the controlfile so postgresql can't start, and
> when done, put it back.

That sounds like a good solution to me. I've made PoC patch for that,
see attached.

The only question is whether pg_checksums should try to move pg_control
back (i) on failure (ii) when interrupted?


Michael

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