Re: Re: Hot Standby query cancellation and Streaming Replication integration

On Fri, 2010-02-26 at 12:02 -0800, Josh Berkus wrote:
> > I don't see a "substantial additional burden" there.  What I would
> > imagine is needed is that the slave transmits a single number back
> > --- its current oldest xmin --- and the walsender process publishes
> > that number as its transaction xmin in its PGPROC entry on the master.
>
> If the main purpose of the slave is long-running queries, though, this
> could cause a lot of bloat on the master.  That's a special case, but a
> reason why we would want to preserve the stop replication functionality.
>

Do we really think that users, using the slave to run long-running
queries is a special case? One of the number one things I can see this
being used for is reporting....

Sincerely,

Joshua D. Drake


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