Re: Additional options for Sync Replication

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>

To: Fujii Masao <masao.fujii@gmail.com>

Cc: Robert Haas <robertmhaas@gmail.com>, Dimitri Fontaine <dimitri@2ndquadrant.fr>, Yeb Havinga <yebhavinga@gmail.com>, Greg Stark <gsstark@mit.edu>, pgsql-hackers <pgsql-hackers@postgresql.org>

Date: 2011-03-30T07:51:56Z

Lists: pgsql-hackers

On Wed, Mar 30, 2011 at 5:29 AM, Fujii Masao <masao.fujii@gmail.com> wrote:

> I'm very excited about new options, especially recv. But I agree with
> Robert and Heikki because what the patch provides looks like new
> feature rather than bug fix. And I think that we still require some
> discussions of the design; how far transactions must wait for sync
> rep in recv mode? In the patch, they wait for WAL to be written in
> the standby, but I think that they should wait until walreceiver has
> recieved WAL instead. That would increase the performance of sync
> rep. Anyway, I don't think now is time to discuss about such a design
> except for bug fix.

Not waiting for write would just be much less safe and would not have
any purpose as a sync rep option.

The difference in time would be very marginal also.

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