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

From Fabien COELHO
Subject Re: Offline enabling/disabling of data checksums
Date
Msg-id alpine.DEB.2.21.1901081614210.32421@lancre
Whole thread Raw
In response to Re: Offline enabling/disabling of data checksums  (Bernd Helmle <mailings@oopsware.de>)
Responses Re: Offline enabling/disabling of data checksums
List pgsql-hackers
>> Adding a new state to ControlFileData which would prevent it from
>> starting?
>
> But then you have to make sure the control flag gets cleared in any
> case pg_verify_checksums crashes somehow or gets SIGKILL'ed ...

The usual approach is a restart with some --force option?

> Setting the checksum flag is done after having finished all blocks, so
> there is no problem.

There is also a problem if the db is started while the checksum is being 
enabled.

> But we need to set this new flag before and reset it afterwards, so in 
> between strange things can happen (as the various calls to exit() within 
> error handling illustrates).

Sure, there is some need for a backup plan if it fails and the control 
file is let in a wrong state.

-- 
Fabien.


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