Re: User Interface for WAL usage data - Mailing list pgsql-hackers

From Justin Pryzby
Subject Re: User Interface for WAL usage data
Date
Msg-id 20200406163420.GE2228@telsasoft.com
Whole thread Raw
In response to Re: User Interface for WAL usage data  (Julien Rouhaud <rjuju123@gmail.com>)
Responses Re: User Interface for WAL usage data  (Amit Kapila <amit.kapila16@gmail.com>)
List pgsql-hackers
On Thu, Apr 02, 2020 at 08:29:31AM +0200, Julien Rouhaud wrote:
> > > "full page records" seems to be showing the number of full page
> > > images, not the record having full page images.
> >
> > I am not sure what exactly is a difference but it is the records
> > having full page images.  Julien correct me if I am wrong.

> Obviously previous complaints about the meaning and parsability of
> "full page writes" should be addressed here for consistency.

There's a couple places that say "full page image records" which I think is
language you were trying to avoid.  It's the number of pages, not the number of
records, no ?  I see explain and autovacuum say what I think is wanted, but
these say the wrong thing?  Find attached slightly larger patch.

$ git grep 'image record'
contrib/pg_stat_statements/pg_stat_statements.c:        int64           wal_num_fpw;    /* # of WAL full page image
recordsgenerated */
 
doc/src/sgml/ref/explain.sgml:      number of records, number of full page image records and amount of WAL

-- 
Justin

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