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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Greg Stark <gsstark@mit.edu>
Cc: Robert Haas <robertmhaas@gmail.com>
Cc: pgsql-hackers@postgresql.org
Subject: Re: time-delayed standbys
Date: Wed, 20 Apr 2011 10:41:31 -0400
Message-ID: <26404.1303310491@sss.pgh.pa.us> (raw)
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Greg Stark <gsstark@mit.edu> writes:
> Ah, so we did put the master's clock in every message?

Yes, we did.

> Then this
> should be simple, no? Just compare the master's timestamp from the
> record to the last master's clock seen in the messages. That sounds
> equivalent but a lot safer than trying to keep a conversion between
> them.

Well, the question is what happens after you stop receiving master
messages.  If you don't make use of the slave's clock somehow,
application of WAL will stop dead in the water, which seems unlikely
to be what's wanted.

			regards, tom lane

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