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(at)2ndquadrant(dot)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(at)2ndquadrant(dot)com>
To: "Takayuki Tsunakawa" <tsunakawa(dot)takay(at)jp(dot)fujitsu(dot)com>
Cc: "ITAGAKI Takahiro" <itagaki(dot)takahiro(at)oss(dot)ntt(dot)co(dot)jp>;
<pgsql-hackers(at)postgresql(dot)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
>
>
>