Re: A new message seems missing a punctuation

At Mon, 19 Feb 2024 10:31:33 +0530, Robert Haas <robertmhaas(at)gmail(dot)com> wrote in
> On Mon, Feb 19, 2024 at 10:10 AM Kyotaro Horiguchi
> <horikyota(dot)ntt(at)gmail(dot)com> wrote:
> > A recent commit (7a424ece48) added the following message:
> >
> > > could not sync slot information as remote slot precedes local slot:
> > > remote slot "%s": LSN (%X/%X), catalog xmin (%u) local slot: LSN
> > > (%X/%X), catalog xmin (%u)
> >
> > Since it is a bit overloaded but doesn't have a separator between
> > "catalog xmin (%u)" and "local slot:", it is somewhat cluttered. Don't
> > we need something, for example a semicolon there to improve
> > readability and reduce clutter?
>
> I think maybe we should even revise the message even more. In most
> places we do not just print out a whole bunch of values, but use a
> sentence to connect them.

Mmm. Something like this?:

"could not sync slot information: local slot LSN (%X/%X) or xmin(%u)
behind remote (%X/%X, %u)"

Or I thought the values could be moved to DETAILS: line.

By the way, the code around the message is as follows.

> /*
> * The remote slot didn't catch up to locally reserved position.
> *
> * We do not drop the slot because the restart_lsn can be ahead of the
> * current location when recreating the slot in the next cycle. It may
> * take more time to create such a slot. Therefore, we keep this slot
> * and attempt the synchronization in the next cycle.
> *
> * XXX should this be changed to elog(DEBUG1) perhaps?
> */
> ereport(LOG,
> errmsg("could not sync slot information as remote slot precedes local slot:"
> " remote slot \"%s\": LSN (%X/%X), catalog xmin (%u) local slot: LSN (%X/%X), catalog xmin (%u)",

If we change this message to DEBUG1, a timeout feature to show a
WARNING message might be needed for DBAs to notice that something bad
is ongoing. However, it doesn't seem appropriate as a LOG message to
me. Perhaps, a LOG message should be more like:

> "LOG: waiting for local slot to catch up to remote"
> "DETAIL: remote slot LSN (%X/%X)....; "

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center