Horton

Re: Standbys, txid_current_snapshot, wraparound

Simon Riggs <simon@2ndquadrant.com>

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From: Simon Riggs <simon@2ndQuadrant.com>
To: Marko Kreen <markokr@gmail.com>
Cc: Daniel Farina <daniel@heroku.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Andrey Velikoredchanin <uncleandyv@gmail.com>
Date: 2012-03-29T11:06:50Z
Lists: pgsql-hackers 
On Thu, Mar 29, 2012 at 11:12 AM, Marko Kreen <markokr@gmail.com> wrote:
> On Thu, Mar 29, 2012 at 10:37:54AM +0100, Simon Riggs wrote:
>> When the standby receives the checkpoint record, it stores the
>> information in 2 places:
>> i) directly into ControlFile->checkPointCopy
>> ii) and then into XLogCtl when a safe restartpoint occurs
>
> In RecoveryRestartPoint() I see:
>
> - memcpy(&XLogCtl->lastCheckPoint, checkPoint, sizeof(CheckPoint));
>
> but I still don't see how are the ckptXid* values updated?
>
> What am I missing?

It's updated on the master and then copied into place.

Patch coming in a few hours.

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