Re: min_safe_lsn column in pg_replication_slots view - Mailing list pgsql-hackers

From Michael Paquier
Subject Re: min_safe_lsn column in pg_replication_slots view
Date
Msg-id 20200620065354.GA5367@paquier.xyz
Whole thread Raw
In response to Re: min_safe_lsn column in pg_replication_slots view  (Amit Kapila <amit.kapila16@gmail.com>)
Responses Re: min_safe_lsn column in pg_replication_slots view  (Michael Paquier <michael@paquier.xyz>)
List pgsql-hackers
On Sat, Jun 20, 2020 at 09:45:52AM +0530, Amit Kapila wrote:
> On Sat, Jun 20, 2020 at 7:12 AM Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
>> I don't disagree with removing the LSN column, but at the same time we
>> need to provide *some* way for users to monitor this, so let's add a
>> function to extract the value they need for that.  It seems simple
>> enough.
>
> Isn't this information specific to checkpoints, so maybe better to
> display in view pg_stat_bgwriter?

Not sure that's a good match.  If we decide to expose that, a separate
function returning a LSN based on the segment number from
XLogGetLastRemovedSegno() sounds fine to me, like
pg_wal_last_recycled_lsn().  Perhaps somebody has a better name in
mind?
--
Michael

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