Re: Hot standby, prepared xacts, locks

On Thu, 2009-10-22 at 09:41 +0300, Heikki Linnakangas wrote:
> Simon Riggs wrote:
> > On Thu, 2009-10-22 at 07:55 +0300, Heikki Linnakangas wrote:
> >> Making some effort to transfer locks instead of acquiring+releasing
> >> would eliminate the need for having extra lock space available when
> >> switching from hot standby mode to normal operation.
> >
> > This isn't very clear. You started by saying you were quite eager to
> > always grant and then release; this sounds like you don't want that now,
> > but you now again like the approach I had already attempted to take.
>
> Yeah, I haven't made up my mind. What's in there now is certainly
> broken, so we need to do something.

Agreed

> The simplest approach

is the best

> would be to
> revert the changes in lock_twophase_recover(), while transfering the
> locks with something like AtPrepare_Locks() would be more robust in the
> face of shared memory shortage.

Will look into it

--
Simon Riggs www.2ndQuadrant.com