Re: recovery getting interrupted is not so unusual as it used to be

On Wed, Jun 2, 2010 at 9:07 PM, Florian Pflug <fgp@phlo.org> wrote:
> On Jun 3, 2010, at 0:58 , Robert Haas wrote:
>> But maybe the message isn't right the first time either.  After all
>> the point of having a write-ahead log in the first place is that we
>> should be able to prevent corruption in the event of an unexpected
>> shutdown.  Maybe the right thing to do is to forget about adding a new
>> state and just remove or change the errhint from these messages:
>
> You've fallen prey to a (very common) miss-interpration of this message. It is not about corruption *caused* by a
crashduring recovery, it's about corruption *causing* the crash. 
>
> I'm not in favor of getting rid of that message entirely, since produces a worthwhile hint if the crash was really
causedby corrupt data. But it desperately needs a better wording that makes cause and effect perfectly clear. That even
youmiss-read it conclusively proves that. 
>
> How about
> "If this has happened repeatedly and without manual intervention, it was probably caused by corrupted data and you
mayneed to restore from backup" 
> for the crash recovery case and
> "If this has happened repeatedly and without manual intervention, it was probably caused by corrupted data and you
mayneed to choose an earlier recovery target" 
> for the PITR case.

Oh.  Well, if that's the case, then I guess I lean toward applying the
patch as-is.  Then there's no need for the caveat "and without manual
intervention".

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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