Re: trivial patch for dynahash logging

Jeff Janes <jeff(dot)janes(at)gmail(dot)com> writes:
> under HASH_STATISTICS, the output reporting "this HTAB" upon destruction is
> pretty useless. Which HTAB would this one be? It is not necessarily the
> most recently created one.

> This makes it output the %p to the actual HTAB, so it can be matched up
> with the logging of the creation.

Seems reasonable, although I wonder why neither of them print the tabname
string. More generally, I see no calls to hash_stats() anywhere except
in hash_destroy(), so wouldn't you need a rather larger patch to make it
actually do anything useful?

> I'm not sure why it bypasses elog. Is that so it can run during start-up
> before elog is active? I'd like to make it go through elog so that
> log_line_prefix are applied, but then it would no longer be a trivial patch.

A quick dig in our git history shows that it was like that in Postgres95,
so the answer is most likely "this code predates elog()". I would think
it'd be a safe assumption that elog is initialized before any hashtables
are created, but certainly you could test that pretty quickly ...

regards, tom lane