Re: Summary and Plan for Hot Standby

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
Cc: pgsql-hackers@postgresql.org
Date: 2009-11-15T19:43:39Z
Lists: pgsql-hackers
On Sun, 2009-11-15 at 21:20 +0200, Heikki Linnakangas wrote:
> Simon Riggs wrote:
> > On Sun, 2009-11-15 at 20:30 +0200, Heikki Linnakangas wrote:
> > 
> >> The LSN doesn't help there, because when an itemid is marked as dead,
> >> the LSN is not updated.
> > 
> > I was thinking we could update the index block LSN without writing WAL
> > using the LSN of the heap block that leads to the killed tuple.
> 
> That can be before the cleanup record we write before we start the index
> vacuum.

Oh well. Strike 1.

But the technique sounds OK, we just need to get the LSN of a HeapInfo
record from somewhere, say, index metapage. Sounds like we need to do
something similar with the xid.

-- 
 Simon Riggs           www.2ndQuadrant.com