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In-Reply-To: 
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From: Amit Kapila <amit.kapila16@gmail.com>
Date: Mon, 27 Sep 2021 10:12:01 +0530
Message-ID: 
 <CAA4eK1JEVoTJNMu94vVdUoak-uefo9V=XJ5bQQ+o47uawDFftg@mail.gmail.com>
Subject: Re: Failed transaction statistics to measure the logical replication
 progress
To: "osumi.takamichi@fujitsu.com" <osumi.takamichi@fujitsu.com>
Cc: Masahiko Sawada <sawada.mshk@gmail.com>,
	"pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
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 <https://www.postgresql.org/message-id/CAA4eK1JEVoTJNMu94vVdUoak-uefo9V%3DXJ5bQQ%2Bo47uawDFftg%40mail.gmail.com>
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On Wed, Sep 22, 2021 at 10:10 AM osumi.takamichi@fujitsu.com
<osumi.takamichi@fujitsu.com> wrote:
>
> Just conducted some cosmetic changes
> and rebased my patch, using v14 patch-set in [1].
>

IIUC, this proposal will allow new xact stats for subscriptions via
pg_stat_subscription. One thing that is not clear to me in this patch
is that why you choose a different way to store these stats than the
existing stats in that view? AFAICS, the other existing stats are
stored in-memory in LogicalRepWorker whereas these new stats are
stored/fetched via stats collector means these will persist. Isn't it
better to be consistent here? I am not sure which is a more
appropriate way to store these stats and I would like to hear your and
other's thoughts on that matter but it appears a bit awkward to me
that some of the stats in the same view are persistent and others are
in-memory.

-- 
With Regards,
Amit Kapila.