Re: Offline enabling/disabling of data checksums
От | Fabien COELHO |
---|---|
Тема | Re: Offline enabling/disabling of data checksums |
Дата | |
Msg-id | alpine.DEB.2.21.1812271206340.32444@lancre обсуждение исходный текст |
Ответ на | Re: Offline enabling/disabling of data checksums (Magnus Hagander <magnus@hagander.net>) |
Ответы |
Re: Offline enabling/disabling of data checksums
|
Список | pgsql-hackers |
>> For enable/disable, while the command is running, it should mark the >> cluster as opened to prevent an unwanted database start. I do not see >> where this is done. >> >> You have pretty much the same class of problems if you attempt to >> start a cluster on which pg_rewind or the existing pg_verify_checksums >> is run after these have scanned the control file to make sure that >> they work on a cleanly-stopped instance. [...] > > I think it comes down to what the outcome is. If we're going to end up with > a corrupt database (e.g. one where checksums aren't set everywhere but they > are marked as such in pg_control) then it's not acceptable. If the only > outcome is the tool gives an error that's not an error and if re-run it's > fine, then it's a different story. ISTM that such an outcome is indeed a risk, as a starting postgres could update already checksummed pages without putting a checksum. It could be even worse, although with a (very) low probability, with updates overwritten on a race condition between the processes. In any case, no error would be reported before much later, with invalid checksums or inconsistent data, or undetected forgotten committed data. -- Fabien.
В списке pgsql-hackers по дате отправления: