Subject: Re: Add Information during standby recovery conflicts
To: Fujii Masao <masao.fujii@oss.nttdata.com>, Masahiko Sawada
	<sawada.mshk@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Kyotaro
 Horiguchi <horikyota.ntt@gmail.com>, Masahiko Sawada
	<masahiko.sawada@2ndquadrant.com>
CC: PostgreSQL-development <pgsql-hackers@postgresql.org>
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From: "Drouvot, Bertrand" <bdrouvot@amazon.com>
Message-ID: <d74412a7-b037-4a49-34a9-491ebba99dd1@amazon.com>
Date: Fri, 8 Jan 2021 07:42:46 +0100
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On 1/8/21 7:24 AM, Fujii Masao wrote:
> CAUTION: This email originated from outside of the organization. Do 
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>
>
> On 2021/01/08 14:02, Drouvot, Bertrand wrote:
>> Hi,
>>
>> On 1/7/21 4:51 PM, Fujii Masao wrote:
>>> Thanks for the review! I pushed the latest patch.
>>>
>> Thanks all of you for your precious help on this patch!
>>
>> The original idea behind this thread has been split into 3 pieces.
>>
>> Pieces 1 (9d0bd95fa90a7243047a74e29f265296a9fc556d) and 2 
>> (0650ff23038bc3eb8d8fd851744db837d921e285) have now been committed, 
>> the last one is to add more information regarding the canceled 
>> statements (if any), like:
>>
>> * What was the blocker(s) doing?
>
> This "canceled statement" is just one that's canceled by recovery 
> conflict?
> If so, the blocker is always the startup process? Sorry maybe I fail to
> understand this idea well..
>
>
By blocker, I meant the one being canceled (I had in mind the startup 
process being the blocked one, not the blocker one). Sorry if i have not 
been clear enough.

As an example, it could provide things like:

2020-06-15 06:48:54.778 UTC [7037] LOG: about to interrupt pid: 7037, 
backend_type: client backend, state: active, wait_event_type: Timeout, 
wait_event: PgSleep, query_start: 2020-06-15 06:48:13.008427+00
2020-06-15 06:48:54.778 UTC [7037] ERROR: canceling statement due to 
conflict with recovery

> Anyway if you post the patch, I'm happy to review that!

Thanks!

Bertrand