Re: [BUG] Checkpointer on hot standby runs without looking checkpoint_segments

Hello,

On Sun, May 13, 2012 at 10:38 PM, Kyotaro HORIGUCHI
<horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp> wrote:
> I've overlooked that startup process of the standby reads
> archives first, and then WAL. But the current patch enables
> progress governing based on checkpoint_segments during archive
> recovery on the standby.

I forcused on WalRcvInProgress again to achieve this. The problem on
using it was its intermittent nature. But using IsStandbyMode to avoid
that turned out to lead another problem.

Now, the introduced function WalRcvStarted() uses WalRcvInProgress to
inform the caller if wal receiver has been started regardless of
current status.

We can avoid accelarated checkpoints before WAL receiver starts, but
checkpoints on WAL streaming will be governed with
checkpoint_segments.

I have not certain answer for the criticism that checkpoint_semgents
should be ignored even when WAL streaming.. Allowing
checkpoint_segments be null to signal no check aganst it? Introduce
another guc variable in bool to instruct to ignore checkpoint_semgnts
on WAL streaming? Or something other?

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center