Re: Load distributed checkpoint

Mr. Riggs,

Thank you for teaching me the following. I seem to have misunderstood.
I'll learn more.

From: "Simon Riggs" <simon@2ndquadrant.com>
> On Fri, 2006-12-08 at 11:05 +0900, Takayuki Tsunakawa wrote:
>> I understand that checkpoints occur during crash
>> recovery and PITR, so time for those operations would get longer.
>
> A restorepoint happens during recovery, not a checkpoint. The
recovery
> is merely repeating the work of the checkpoint that occurred in the
> original WAL stream. Elongating the checkpoint would not have any
effect
> on a restorepoint: we only record the checkpoint when it is complete
and
> we only create a restorepoint when we see the checkpoint record.


Regards,

----- Original Message ----- 
From: "Simon Riggs" <simon@2ndquadrant.com>
To: "Takayuki Tsunakawa" <tsunakawa.takay@jp.fujitsu.com>
Cc: "ITAGAKI Takahiro" <itagaki.takahiro@oss.ntt.co.jp>;
<pgsql-hackers@postgresql.org>
Sent: Monday, December 11, 2006 6:30 PM
Subject: Re: [HACKERS] Load distributed checkpoint


> On Fri, 2006-12-08 at 11:05 +0900, Takayuki Tsunakawa wrote:
>> I understand that checkpoints occur during crash
>> recovery and PITR, so time for those operations would get longer.
>
> A restorepoint happens during recovery, not a checkpoint. The
recovery
> is merely repeating the work of the checkpoint that occurred in the
> original WAL stream. Elongating the checkpoint would not have any
effect
> on a restorepoint: we only record the checkpoint when it is complete
and
> we only create a restorepoint when we see the checkpoint record.
>
> Crash recovery and PITR use almost exactly the same code path (by
> design), so there isn't anything special to say about PITR either.
>
> -- 
>  Simon Riggs
>  EnterpriseDB   http://www.enterprisedb.com
>
>
>