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Message-ID: <725e3117-2a0d-460a-a53c-a487fa98e1fe@oss.nttdata.com>
Date: Wed, 18 Sep 2024 19:21:10 +0900
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Subject: Re: May be BUG. Periodic burst growth of the checkpoint_req counter
 on replica.
Content-Language: en-US
From: Fujii Masao <masao.fujii@oss.nttdata.com>
To: "Anton A. Melnikov" <a.melnikov@postgrespro.ru>,
 Alexander Korotkov <aekorotkov@gmail.com>
Cc: Magnus Hagander <magnus@hagander.net>,
 "Anton A. Melnikov" <aamelnikov@inbox.ru>, Andres Freund
 <andres@anarazel.de>, Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
 pgsql-hackers@lists.postgresql.org
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On 2024/09/17 11:47, Fujii Masao wrote:
> 
> 
> On 2024/09/16 23:30, Anton A. Melnikov wrote:
>> +1
>> This idea seems quite tenable to me.
>>
>> There is a small clarification. Now if there were no skipped restartpoints then
>> restartpoints_done will be equal to restartpoints_timed + restartpoints_req.
>> Similar for checkpoints.
>> So i tried to introduce num_done counter for checkpoints in the patch attached.
> 
> Thanks for the patch! I believe this change is targeted for v18. For v17, however,
> we should update the description of num_timed in the documentation. Thought?
> Here's a suggestion:
> 
> "Number of scheduled checkpoints due to timeout. Note that checkpoints may be
> skipped if the server has been idle since the last one, and this value counts
> both completed and skipped checkpoints."

Patch attached.
Unless there are any objections, I plan to commit this and back-patch it to v17.

Regards,

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

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