Re: suppressing useless wakeups in logical/worker.c

On Thu, Jan 26, 2023 at 03:04:30PM -0500, Tom Lane wrote:
> Nathan Bossart <nathandbossart@gmail.com> writes:
>> I wonder if we should explicitly reject negative timestamps to eliminate
>> any chance of int64 overflow, too.
> 
> Hmm.  I'm disinclined to add an assumption that the epoch is in the past,
> but I take your point that the subtraction would overflow with
> TIMESTAMP_INFINITY and a negative finite timestamp.  Maybe we should
> make use of pg_sub_s64_overflow()?

That would be my vote.  I think the 'diff <= 0' check might need to be
replaced with something like 'start_time > stop_time' so that we return 0
for the underflow case.

-- 
Nathan Bossart
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