Re: "using previous checkpoint record at" maybe not the greatest idea? - Mailing list pgsql-hackers

From Jim Nasby
Subject Re: "using previous checkpoint record at" maybe not the greatest idea?
Date
Msg-id 56B3E393.8080302@BlueTreble.com
Whole thread Raw
In response to Re: "using previous checkpoint record at" maybe not the greatest idea?  ("David G. Johnston" <david.g.johnston@gmail.com>)
List pgsql-hackers
On 2/4/16 5:09 PM, David G. Johnston wrote:
>
>     What the 2nd para in the documentation is saying is something different:
>     it is talking about reading all the pg_xlog files (in reverse order),
>     which is not pg_control, and see what checkpoint records are there, then
>     figure out which one to use.
>
>
> Yes, I inferred something that obviously isn't true - that the system
> doesn't go hunting for a valid checkpoint to begin recovery from.  While
> it does not do so in the case of a corrupted pg_control file I further
> assumed it never did.  That would be because the documentation doesn't
> make the point of stating that two checkpoint positions exist and that
> PostgreSQL will try the second one if the first one proves unusable.
> Given the topic of this thread that omission makes the documentation
> out-of-date.  Maybe its covered elsewhere but since this section
> addresses locating a starting point I would expect any such description
> ​to be here as well.

Yeah, I think we should fix the docs. Especially since I imagine that if 
you're reading that part of the docs you're probably having a really bad 
day, and bad info won't help you...
-- 
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com



pgsql-hackers by date:

Previous
From: Antonin Houska
Date:
Subject: Re: UNIQUE capability to hash indexes
Next
From: Jim Nasby
Date:
Subject: Re: "using previous checkpoint record at" maybe not the greatest idea?