I wrote:
> Oleg Bartunov <oleg@sai.msu.su> writes:
>> It's interesting, that process with pid 701 migrates from
>> (postmaster) to postgres with normal ps output !
> Yes, that's pretty strong evidence in favor of my theory (that these
> processes are just new backends that haven't received a command yet).
Nope, that theory is all wet --- the backend definitely does
PS_SET_STATUS("idle") before it waits for a query. Something is
*really* peculiar here, since your backtrace shows that the backend
has reached the point of waiting for client input. It is not possible
to get there without having done PS_SET_STATUS. So why does the process
still show up as "(postmaster)" in ps? Something is flaky about your
system's support of ps status setting, I think.
regards, tom lane