Re: pg_rewind in contrib

On 01/06/2015 03:39 PM, Peter Eisentraut wrote:
> I applaud the ingenuity on all levels in this patch.  But it seems to me
> that there is way too much backend knowledge encoded and/or duplicated
> in a front-end program.
>
> If this ends up shipping, it's going to be a massively popular tool.  I
> see it as a companion to pg_basebackup.  So it should sort of work the
> same way.  One problem is that it doesn't use the replication protocol,
> so the setup is going to be inconsistent with pg_basebackup.  Maybe the
> replication protocol could be extended to provide the required data.
> Maybe something as simple as "give me this file" would work.
>
> That might lose the local copy mode, but how important is that?
> pg_basebackup doesn't have that mode.  In any case, the documentation
> doesn't explain this distinction.  The option documentation is a bit
> short in any case, but it's not clear that you can choose between local
> and remote mode.
>
> The test suite should probably be reimplemented in Perl.  (I might be
> able to help.)  Again, ingenious, but it's very hard to follow the
> sequence of what is being tested.  And some Windows person is going to
> complain. ;-)
>
> Also, since you have been maintaining this tool for a while, what is the
> effort for maintaining it from version to version?
>
>


I also think it's a great idea. But I think we should consider the name 
carefully. pg_resync might be a better name. Strictly, you might not be 
quite rewinding, AIUI.

cheers

andrew