Re: Synchronous replication - Mailing list pgsql-hackers

From Heikki Linnakangas
Subject Re: Synchronous replication
Date
Msg-id 4C4037E6.1000300@enterprisedb.com
Whole thread Raw
In response to Re: Synchronous replication  (Fujii Masao <masao.fujii@gmail.com>)
Responses Re: Synchronous replication
Re: Synchronous replication
List pgsql-hackers
On 16/07/10 10:40, Fujii Masao wrote:
> So we should always prevent the standby from applying any WAL in pg_xlog
> unless walreceiver is in progress. That is, if there is no WAL available
> in the archive, the standby ignores pg_xlog and starts walreceiver
> process to request for WAL streaming.

That completely defeats the purpose of storing streamed WAL in pg_xlog 
in the first place. The reason it's written and fsync'd to pg_xlog is 
that if the standby subsequently crashes, you can use the WAL from 
pg_xlog to reapply the WAL up to minRecoveryPoint. Otherwise you can't 
start up the standby anymore.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com


pgsql-hackers by date:

Previous
From: Martin Pihlak
Date:
Subject: Re: log files and permissions
Next
From: Paul Fariello
Date:
Subject: dot to be considered as a word delimiter?