Re: Redesigning checkpoint_segments

On 06/26/2015 03:40 PM, Robert Haas wrote:
> Actually, I've seen a number of presentations indicating
> that the pacing of checkpoints is already too aggressive near the
> beginning, because as soon as we initiate the checkpoint we have a
> storm of full page writes.  I'm sure we can come up with arbitrarily
> complicated systems to compensate for this, but something simple might
> be to calculate progress done+adjust/total+adjust rather than
> done/total.  If you let adjust=total/9, for example, then you
> essentially start the progress meter at 10% instead of 0%.  Even
> something that simple might be an improvement.

Yeah, but that's an unrelated issue. This was most recently discussed at 
http://www.postgresql.org/message-id/CAKHd5Ce-bnD=gEEdtXiT2_AY7shquTKd0yHXXk5F4zVEKRPX-w@mail.gmail.com. 
I posted a simple patch there - review and testing is welcome ;-).

- Heikki