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Date: Fri, 4 Feb 2022 10:59:04 +0900
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Subject: Re: Add checkpoint and redo LSN to LogCheckpointEnd log message
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To: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
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From: Fujii Masao <masao.fujii@oss.nttdata.com>
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On 2022/02/03 15:50, Kyotaro Horiguchi wrote:
> On way to take. In that case should we log something like
> "Restartpoint canceled" or something?

+1


> By the way, restart point should start only while recoverying, and at
> the timeof the start both checkpoint.redo and checkpoint LSN are
> already past. We shouldn't update minRecovery point after promotion,
> but is there any reason for not updating the checkPoint and
> checkPointCopy?  If we update them after promotion, the
> which-LSN-to-show problem would be gone.

I tried to find the reason by reading the past discussion, but have not found that yet.

If we update checkpoint and REDO LSN at pg_control in that case, we also need to update min recovery point at pg_control? Otherwise the min recovery point at pg_control still indicates the old LSN that previous restart point set.

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION