Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication. - Mailing list pgsql-hackers

From Greg Stark
Subject Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.
Date
Msg-id AANLkTimVQe4RNqG6jb4XgxSxe2u_3oh+8Jzssn5jDE65@mail.gmail.com
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In response to Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.
List pgsql-hackers
On Thu, Mar 17, 2011 at 5:46 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> What makes more sense to me after having thought about this more
> carefully is to simply make a blanket rule that when
> synchronous_replication=on, synchronous_commit has no effect.  That is
> easy to understand and document.

For what it's worth "has no effect" doesn't make much sense to me.
It's a boolean, either commits are going to block or they're not.

What happened to the idea of a three-way switch?

synchronous_commit = off
synchronous_commit = disk
synchronous_commit = replica

With "on" being a synonym for "disk" for backwards compatibility.

Then we could add more options later for more complex conditions like
waiting for one server in each data centre or waiting for one of a
certain set of servers ignoring the less reliable mirrors, etc.

--
greg


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