Re: Standby catch up state change - Mailing list pgsql-hackers

From Pavan Deolasee
Subject Re: Standby catch up state change
Date
Msg-id CABOikdNz0SP=F09neaDq=KjWU64JowsfjCe78vi4UadGZ1QuRw@mail.gmail.com
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In response to Re: Standby catch up state change  (Andres Freund <andres@2ndquadrant.com>)
Responses Re: Standby catch up state change  (Andres Freund <andres@2ndquadrant.com>)
List pgsql-hackers

On Tue, Oct 15, 2013 at 4:16 PM, Andres Freund <andres@2ndquadrant.com> wrote:
 I don't think delaying the message is a good
idea.

Comment in walsender.c says:

            /*
             * If we're in catchup state, move to streaming.  This is an
             * important state change for users to know about, since before
             * this point data loss might occur if the primary dies and we
             * need to failover to the standby.
             */

IOW it claims no data loss will occur after this point. But if the WAL is cached on the master side, isn't this a false claim i.e. the data loss can still occur even after master outputs the log message and changes the state to streaming. Or am I still getting it wrong ?

Thanks,
Pavan
--
Pavan Deolasee
http://www.linkedin.com/in/pavandeolasee

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