Re: Performance degradation in commit ac1d794

Noah Misch <noah(at)leadboat(dot)com> writes:
> On Tue, May 31, 2016 at 10:09:05PM -0400, Robert Haas wrote:
>> What I *think* is going on here is:
>> - ac1d794 lowered performance
>> - backend_flush_after with a non-zero default lowered performance with
>> a vengeance
>> - 98a64d0 repaired the damage done by ac1d794, or much of it, but
>> Mithun couldn't see it in his benchmarks because backend_flush_after>0
>> is so bad

> Ashutosh Sharma's measurements do bolster that conclusion.

>> That could be wrong, but I haven't seen any evidence that it's wrong.
>> So I'm inclined to say we should just move this open item back to the
>> CLOSE_WAIT list (adding a link to this email to explain why we did
>> so). Does that work for you?

> That works for me.

Can we make a note to re-examine this after the backend_flush_after
business is resolved? Or at least get Mithun to redo his benchmarks
with backend_flush_after set to zero?

regards, tom lane