Re: min_safe_lsn column in pg_replication_slots view

Amit Kapila <amit.kapila16@gmail.com>

From: Amit Kapila <amit.kapila16@gmail.com>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
Cc: Fujii Masao <masao.fujii@oss.nttdata.com>, Michael Paquier <michael@paquier.xyz>, Kyotaro Horiguchi <horikyota.ntt@gmail.com>, pgsql-hackers <pgsql-hackers@lists.postgresql.org>
Date: 2020-07-04T06:18:47Z
Lists: pgsql-hackers
On Wed, Jul 1, 2020 at 8:44 PM Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
>
> On 2020-Jul-01, Amit Kapila wrote:
>
> > Okay, but do we think it is better to display this in
> > pg_replication_slots or some new view like pg_stat_*_slots as being
> > discussed in [1]?  It should not happen that we later decide to move
> > this or similar stats to that view.
>
> It seems that the main motivation for having some counters in another
> view is the ability to reset them; and resetting this distance value
> makes no sense, so I think it's better to have it in
> pg_replication_slots.
>

Fair enough.  It would be good if we can come up with something better
than 'distance' for this column.  Some ideas safe_wal_limit,
safe_wal_size?

-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com



Commits

  1. Fix uninitialized value in segno calculation

  2. Morph pg_replication_slots.min_safe_lsn to safe_wal_size