From: "myungkyu.lim" <myungkyu.lim@samsung.com>
To: "'Michael Paquier'" <michael@paquier.xyz>
Cc: "'Masahiko Sawada'" <sawada.mshk@gmail.com>, "'PostgreSQL-development'"
	<pgsql-hackers@postgresql.org>, <woosung.sohn@samsung.com>,
	<don.hong@samsung.com>
In-Reply-To: <20181204060657.GA6859@paquier.xyz>
Subject: RE: [Todo item] Add entry creation timestamp column to
 pg_stat_replication
Date: Tue, 4 Dec 2018 16:24:25 +0900
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>> I have been looking at this patch more in-depth, and you missed one
>> critical thing: hot standby feedback messages also include the
>> timestamp the client used when sending the message, so if we want to
>> track the latest time when a message has been sent we should track it
>> as much as the timestamp from status update messages.
>>
>> Fixing that and updating a couple of comments and variables, I am
>> finishing with the attached.  Thoughts?

Thanks! I missed it..:(

>Another thing which is crossing my mind is if it would make sense to report
>the timestamp of the last HS feedback message and the timestamp of the last
>status update message into two separate columns.  As the point of this
>field is to help with the debugging of mostly idle systems it seems to me
>that merging both is fine, but I'd like to hear extra opinions about that.

I think purpose of this field, 
that react interval check and debugging on idle system.
So, merging both is better.
(Is 'Reply' and 'HSFeedback' worth measuring separately?)