Re: request for new parameter for disable promote (slave only mode) - Mailing list pgsql-hackers

From Robert Haas
Subject Re: request for new parameter for disable promote (slave only mode)
Date
Msg-id CA+TgmobfQSGCYhqGUQu20QtmXAJES=611qG8JU0onZtSBvfmeA@mail.gmail.com
Whole thread Raw
In response to request for new parameter for disable promote (slave only mode)  (Ioseph Kim <pgsql-kr@postgresql.kr>)
List pgsql-hackers
On Fri, Jul 27, 2018 at 12:05 PM, Ioseph Kim <pgsql-kr@postgresql.kr> wrote:
> I want to build one master & multi slave environments to use physical replication.
> Slave nodes have low hardware spec, so I changed max_connection server parameters, and try start slave node.
> But I could not start slave nodes,
> because CheckRequiredParameterValues function (in src/backend/access/transam/xlog.c) reject to set less values then
master’svalues. 
>
> It is maybe,
> This concept is base on some slave node can be promte master.

No, it's because the machinery that computes MVCC snapshots on slaves
relies on max_connections being set high enough.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


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