Re: Skip checkpoint on promoting from streaming replication

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
Cc: masao.fujii@gmail.com, pgsql-hackers@postgresql.org
Date: 2012-08-09T09:45:55Z
Lists: pgsql-hackers
On 22 June 2012 05:03, Kyotaro HORIGUCHI
<horiguchi.kyotaro@lab.ntt.co.jp> wrote:

>    I hope this is promising.

I've reviewed this and thought about it over some time.

At first I was unhappy that you'd removed the restriction that
timelines only change on a shutdown checkpoint. But the reality is
timelines change at any point in the WAL stream - the only way to tell
between end of WAL and a timeline change is by looking for later
timelines.

The rest of the logic seems OK, but its a big thing we're doing here
and so it will take longer yet. Putting all the theory into comments
in code would certainly help here.

I don't have much else to say on this right now. I'm not committing
anything on this now since I'm about to go on holiday, but I'll be
looking at this when I get back.

For now, I'm going to mark this as Returned With Feedback, but please
don't be discouraged by that.

-- 
 Simon Riggs                   http://www.2ndQuadrant.com/
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