Re: btree_gist valgrind warnings about uninitialized memory

On 2014-05-14 12:20:55 -0400, Tom Lane wrote:
> Andres Freund <andres@2ndquadrant.com> writes:
> > On 2014-05-14 10:07:18 -0400, Tom Lane wrote:
> >> I think that's an OK restriction as long as we warn people about it
> >> (you could update a replication pair as long as you shut them both
> >> down cleanly at the same time, right?).  Can the WAL replay routine
> >> be made to detect incompatible records?
> 
> > We could just bump the wal version. Somewhat surprisingly that works if
> > both nodes are shutdown cleanly (primary first)... But the errors about
> > it are really ugly (will moan about unusable checkpoints), so it's
> > probably not a good idea. Especially as it'll make it an issue for all
> > users, not just the ones creating spgist indexes.
> 
> Yeah, I don't think we want to bump the WAL version code post-beta1.
> 
> Probably better to assign the modified spgist record a new xl_info ID
> number, so that a beta1 slave would throw an error for it.

Since that ship has now sailed...? It's imo bad form to release a new
version that overwrites the stack and heap, even if we can't see a
concrete danger.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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