On Tue, 2024-02-06 at 12:29 -0500, Tom Lane wrote:
> Nathan Bossart <nathandbossart@gmail.com> writes:
> > It looks like there are two ideas:
> > [...]
> > * Set log_lock_waits on by default. The folks on this thread seem to
> > support this idea, but given the lively discussion for enabling
> > log_checkpoints by default [0], I'm hesitant to commit something like
> > this without further community discussion.
>
> I was, and remain, of the opinion that that was a bad idea that
> we'll eventually revert, just like we previously got rid of most
> inessential log chatter in the default configuration. So I doubt
> you'll have much trouble guessing my opinion of this one. I think
> the default logging configuration should be chosen with the
> understanding that nobody ever looks at the logs of most
> installations, and we should be more worried about their disk space
> consumption than anything else. Admittedly, log_lock_waits is less
> bad than log_checkpoints, because no such events will occur in a
> well-tuned configuration ... but still, it's going to be useless
> chatter in the average installation.
Unsurprisingly, I want to argue against that.
You say that it is less bad than "log_checkpoints = on", and I agree.
I can't remember seeing any complaints by users about
"log_checkpoints", and I predict that the complaints about
"log_lock_waits = on" will be about as loud.
I am all for avoiding useless chatter in the log. In my personal
experience, that is usually "database typo does not exist" and
constraint violation errors. I always recommend people to enable
"log_lock_waits", and so far I have not seen it spam the logs.
I agree that usually nobody ever looks into the log file. The
time when people *do* look into the log file is when they encounter
trouble, and my stance is that the default configuration should be
such that the log contains clues as to what may be the problem.
If a statement sometimes takes unreasonably long, it is very
valuable corroborative information that the statement occasionally
waits more than a second for a lock.
Yours,
Laurenz Albe
