Re: "could not reattach to shared memory" on buildfarm member dory

Greetings,

* Tom Lane (tgl@sss.pgh.pa.us) wrote:
> So far, dory has failed three times with essentially identical symptoms:
>
> 2018-04-23 19:57:10.624 GMT [2240] FATAL:  could not reattach to shared memory (key=0000000000000190, addr=00000000018E0000): error code 487
> 2018-04-23 15:57:10.657 EDT [8836] ERROR:  lost connection to parallel worker
> 2018-04-23 15:57:10.657 EDT [8836] STATEMENT:  select count(*) from tenk1 group by twenty;
> 2018-04-23 15:57:10.660 EDT [3820] LOG:  background worker "parallel worker" (PID 2240) exited with exit code 1
>
> Now how can this be?  We've successfully reserved and released the address
> range we want to use, so it *should* be free at the instant we try to map.

Yeah, that's definitely interesting.

> I guess the good news is that we're seeing this in a reasonably
> reproducible fashion, so there's some hope of digging down to find
> out the actual cause.

I've asked Heath to take a look at the system again and see if there's
any Windows logs or such that might help us understand what's happening.
AV was disabled on the box, so don't think it's that, at least.