Re: Latest version of Hot Standby patch
Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
From: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
To: Simon Riggs <simon@2ndQuadrant.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2008-12-19T11:58:30Z
Lists: pgsql-hackers
Simon Riggs wrote: > On Fri, 2008-12-19 at 10:59 +0200, Heikki Linnakangas wrote: >> Simon Riggs wrote: >>> * corner case behaviour of backendids - bgwriter writes checkpoint WAL >>> records. Has no backendid, but needs a slotid (possibly others) >> Why does bgwriter need a slotid? It doesn't run any transactions. >> >>> * slotids are assigned once and never changed, so allowing them to be >>> used as array lookups directly >> So are backend ids. > > I'm a little hazy, to be sure. I'm pretty sure there was a blocker, but > if I cannot recall it we should assume it doesn't exist. > > Where are you going with the thought? Remove slotId from each proc and > then use backendId to identify the recovery proc? Yep. Well, to be honest, I don't much like the whole notion of tracking the slots. I think we should just rely on the XLOG_RECOVERY_END records to purge stale PGPROC entries, belonging to backends that died without writing an abort record. -- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com