Re: remove checkpoint_warning

Craig Ringer <craig@2ndquadrant.com>

From: Craig Ringer <craig@2ndquadrant.com>
To: Stephen Frost <sfrost@snowman.net>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Alvaro Herrera <alvherre@2ndquadrant.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2016-07-12T01:32:18Z
Lists: pgsql-hackers
On 11 July 2016 at 22:25, Stephen Frost <sfrost@snowman.net> wrote:

> * Tom Lane (tgl@sss.pgh.pa.us) wrote:
> > Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> > > the checkpoint_warning feature was added by commit
> 2986aa6a668bce3cfb836
> > > in November 2002 when we didn't have any logging of checkpointing at
> > > all.  I propose to remove it: surely anyone who cares about analyzing
> > > checkpointing behavior nowadays is using the log_checkpoint feature
> > > instead, which contains much more detail.  The other one is just noise
> > > now, and probably ignored amidst the number of other warning traffic.
> >
> > Hmm, not sure.  ISTM log_checkpoint is oriented to people who know what
> > they are doing, whereas checkpoint_warning is more targeted to trying
> > to help people who don't.  Perhaps you could make an argument that
> > checkpoint_warning is useless because the people whom it's meant to help
> > won't notice the warning anyway --- but I doubt that it's been
> > "superseded" by log_checkpoint, because the latter would only be enabled
> > by people who already have a clue that checkpoint performance is
> something
> > to worry about.
> >
> > Or in short, this may be a fine change to make, but I don't like your
> > argument for it.
>
> I don't agree that it's sensible to get rid of.  Having just
> log_checkpoints will have the logs filled with checkpoints starting
> because of XLOG, but there's no indication of that being a bad thing.
>
>
Also, the warning is greppable-for and easily spotted by log ingesting
tools. I see no real reason to remove it.



-- 
 Craig Ringer                   http://www.2ndQuadrant.com/
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