Re: termination of backend waiting for sync rep generates a junk log message

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Tue, Oct 18, 2011 at 11:27 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> One thing worth asking is why we're willing to violate half a dozen
>> different coding rules if we see ProcDiePending, yet we're perfectly
>> happy to rely on the client understanding a WARNING for the
>> QueryCancelPending case. Another is whether this whole function isn't
>> complete BS in the first place, since it appears to be coded on the
>> obviously-false assumption that nothing it calls can throw elog(ERROR)
>> --- and of course, if any of those functions do throw ERROR, all the
>> argumentation here goes out the window.

> Well, there is a general problem that anything which throws an ERROR
> too late in the commit path is Evil; and sync rep makes that worse to
> the extent that it adds more stuff late in the commit path, but it
> didn't invent the problem. What it did do is add stuff late in the
> commit path that can block for a potentially unbounded period of time,
> and I don't see that there are any solutions to that problem that
> aren't somewhat grotty.

No doubt, but fantasizing about what you are or are not controlling
doesn't help ... and AFAICT this code is mostly fantasy. Anyway,
I don't have a better proposal right offhand; will think about it.

regards, tom lane