Re: Proposal for 9.1: WAL streaming from WAL buffers

On Mon, 2010-06-21 at 18:08 +0900, Fujii Masao wrote:

> The problem is not that the master streams non-fsync'd WAL, but that the
> standby can replay that. So I'm thinking that we can send non-fsync'd WAL
> safely if the standby makes the recovery wait until the master has fsync'd
> WAL. That is, walsender sends not only non-fsync'd WAL but also WAL flush
> location to walreceiver, and the standby applies only the WAL which the
> master has already fsync'd. Thought?

Yes, good thought. The patch just applied seems too much.

I had the same thought, though it would mean you'd need to send two xlog
end locations, one for write, one for fsync. Though not really clear why
we send the "current end of WAL on the server" anyway, so maybe we can
just alter that.

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