On Thu, 2008-12-18 at 15:13 +0200, Heikki Linnakangas wrote: > Can't we use the existing backendid in place of the slot id? > > (sorry if this has been discussed already; can't remember)
Exactly the sort of question we need, but unfortunately I'm a little hazy, but I just woke up some maybe some coffee will change that answer later. They're certainly related and I did try it initially. SlotId was not present in early versions of the patch up to 13 Oct, though backendId was. IIRC there were a couple of reasons * corner case behaviour of backendids - bgwriter writes checkpoint WAL records. Has no backendid, but needs a slotid (possibly others) * slotids are assigned once and never changed, so allowing them to be used as array lookups directly I think it would be possible to use slotids as backendids, but not the other way around. Anyway, seemed like a great way to induce bugs into the sinval code, so I didn't try too hard to make them identical. -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
