On 2015-04-07 17:22:12 +0800, Craig Ringer wrote:
> It might be a good idea to apply this if nothing better is forthcoming.
> Logical decoding in WALsenders is broken at the moment.
Yes.
> Otherwise it needs to go on the 9.5 blockers list.
>
> But could we get rid of those active_count manipulations too? Could you
> > replace the SnapBuildSnap[Inc|Dec]Refcount calls with
> > [Un]RegisterSnapshot()?
> >
>
> It would be interesting to know why it was done that way in the first
> place, rather than using the snapshot management infrastructure.
Because the snapshot tracking infrastructure isn't particularly
suitable. These snapshots are much longer lived; they span transactions
and such. Nothing snapmgr.c is made for. It seemed more
complicated/bug-prone to change snapmgr.c to support a foreign use case.
Greetings,
Andres Freund
