Re: silent data loss with ext4 / all current versions

On 01/25/2016 08:30 AM, Michael Paquier wrote:
> On Fri, Jan 22, 2016 at 9:32 PM, Michael Paquier
> <michael(dot)paquier(at)gmail(dot)com> wrote:

,,,

>> My first line of thoughts after looking at the patch is that I am
>> not against adding those fsync calls on HEAD as there is roughly
>> an advantage to not go back to recovery in most cases and ensure
>> consistent names, but as they do not imply any data loss I would
>> not encourage a back-patch. Adding them seems harmless at first
>> sight I agree, but those are not actual bugs.
>
> OK. It is true that PGDATA would be fsync'd in 4 code paths with your
> patch which are not that much taken:
> - Renaming tablespace map file and backup label file (three times)
> - Renaming to recovery.done
> So, what do you think about the patch attached? Moving the calls into
> the critical sections is not really necessary except when installing a
> new segment.

Seems OK to me. Thanks for the time and improvements!

Tomas

--
Tomas Vondra http://www.2ndQuadrant.com
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