Re: select_parallel test failure: gather sometimes losing tuples (maybe during rescans)?

On 03/04/2018 04:11 AM, Thomas Munro wrote:
> On Sun, Mar 4, 2018 at 4:07 PM, Tomas Vondra
> <tomas.vondra@2ndquadrant.com> wrote:
>> I've started "make check" with parallel_schedule tweaked to contain many
>> select_parallel runs, and so far I've seen a couple of failures like
>> this (about 10 failures out of 1500 runs):
>>
>>   select count(*) from tenk1, tenk2 where tenk1.hundred > 1 and
>> tenk2.thousand=0;
>> ! ERROR:  lost connection to parallel worker
>>
>> I have no idea why the worker fails (no segfaults in dmesg, nothing in
>> posgres log), or if it's related to the issue discussed here at all.
> 
> That sounds like the new defences from 2badb5afb89cd569500ef7c3b23c7a9d11718f2f.
> 

Yeah. But I wonder why the worker fails at all, or how to find that.


-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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