Re: max_slot_wal_keep_size and wal_keep_segments

On Wed, Jul  1, 2020 at 01:18:06PM -0400, David Steele wrote:
> On 7/1/20 10:54 AM, Alvaro Herrera wrote:
> > On 2020-Jul-01, Fujii Masao wrote:
> > 
> > > On 2020/07/01 12:26, Alvaro Herrera wrote:
> > > > On 2020-Jun-30, Fujii Masao wrote:
> > > > 
> > > > > When I talked about max_slot_wal_keep_size as new feature in v13
> > > > > at the conference, I received the question like "Why are the units of
> > > > > setting values in max_slot_wal_keep_size and wal_keep_segments different?"
> > > > > from audience. That difference looks confusing for users and
> > > > > IMO it's better to use the same unit for them. Thought?
> > > > 
> > > > Do we still need wal_keep_segments for anything?
> > > 
> > > Yeah, personally I like wal_keep_segments because its setting is very
> > > simple and no extra operations on replication slots are necessary.
> > 
> > Okay.  In that case I +1 the idea of renaming to wal_keep_size.
> 
> +1 for renaming to wal_keep_size.

We have the following wal*size GUC settings:

	SELECT name FROM pg_settings WHERE name LIKE '%wal%size%';
	          name
	------------------------
	 max_slot_wal_keep_size
	 max_wal_size
	 min_wal_size
	 wal_block_size
	 wal_segment_size

Does wal_keep_size make sense here?

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EnterpriseDB                             https://enterprisedb.com

  The usefulness of a cup is in its emptiness, Bruce Lee