Re: Proposing pg_hibernate

On 2014-06-04 10:24:13 +0530, Amit Kapila wrote:
> On Tue, Jun 3, 2014 at 5:43 PM, Gurjeet Singh <gurjeet(at)singh(dot)im> wrote:
> > On Tue, Jun 3, 2014 at 7:57 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> > > It seems like it would be best to try to do this at cluster startup
> > > time, rather than once recovery has reached consistency. Of course,
> > > that might mean doing it with a single process, which could have its
> > > own share of problems. But I'm somewhat inclined to think that if
> > > recovery has already run for a significant period of time, the blocks
> > > that recovery has brought into shared_buffers are more likely to be
> > > useful than whatever pg_hibernate would load.
> >
> > I am not absolutely sure of the order of execution between recovery
> > process and the BGWorker, but ...
> >
> > For sizeable shared_buffers size, the restoration of the shared
> > buffers can take several seconds.
>
> Incase of recovery, the shared buffers saved by this utility are
> from previous shutdown which doesn't seem to be of more use
> than buffers loaded by recovery.

Why? The server might have been queried if it's a hot standby one?

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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