"George Pavlov" <gpavlov@mynewplace.com> writes:
>> It'd be interesting to verify whether it's the same on
>> George's machine though.
> Let me know how to test this.
Identify the PID of one of your active backends (from "ps" or by looking
in pg_stat_activity), and then run
strace -p backend-pid-here 2>tmpfile
You'll need to do that as either root or postgres. Let it run for a
minute or three, preferably long enough to capture some long log
messages being emitted by that backend. (Bonus points if you can
capture one that's actually intermixed with others in the log, but
that might take some luck.) Stop it with control-C whenever you get
bored, and then grep through the tmpfile for lines beginning "write(2,".
It should be pretty clear whether log messages are being sent as single
or multiple write() operations.
regards, tom lane