Re: pg_basebackup may fail to send feedbacks.

Hello,

At Wed, 4 Feb 2015 19:22:39 +0900, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote in <CAHGQGwGudGCMnHZinkd37i+JijDkruEcrea1NCRs1MMtE3rOFQ(at)mail(dot)gmail(dot)com>
> On Wed, Feb 4, 2015 at 4:58 PM, Kyotaro HORIGUCHI
> <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp> wrote:
> > I'm very sorry for confused report. The problem found in 9.4.0
> > and the diagnosis was mistakenly done on master.
> >
> > 9.4.0 has no problem of feedback delay caused by slow xlog
> > receiving on pg_basebackup mentioned in the previous mail. But
> > the current master still has this problem.
>
> Seems walreceiver has the same problem. No?

pg_receivexlog.c would have the same problem since it uses the
same function with pg_basebackup.c.

The correspondent of HandleCopyStream in wansender is
WalReceiverMain, and it doesn't seem to have the same kind of
loop shown below. It seems to surely send feedback per one
record.

| r = stream_reader();
| while (r > 0)
| {
| ... wal record processing stuff without sending feedback..
| r = stream_reader();
| }

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center