Re: Parameter name standby_mode

On Thu, Apr 1, 2010 at 6:04 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> I wouldn't recommend setting up a standby server like that, but it's not
>> totally unreasonable. So the standby always has a potential source of
>> WAL, pg_xlog.
>
> OK.

OK, too. I turn down the patch.

> Is it reasonable to think that we can find a way to make it not print
> the duplicate messages over and over again?
>
> LOG:  record with zero length at 0/3006B28
>
> Maybe only print that if the location has advanced since the last such message?

Agreed. But what log message is repeated depends on the situation.
So message without any location might be output. BTW, In my testing,
the following message was repeated.

LOG: invalid magic number 0000 in log file 0, segment 14, offset 9617408

> Should we make it shut down if it can't immediately read enough WAL to
> get to a consistent state, or just figure it's the user's job to fix
> it?

I think that it's difficult for the user to fix it. So I agree to shut
down the server in that case, i.e., throw a FATAL when an invalid WAL
record is found and recovery hasn't reached the safe starting point
even if neither primary_conninfo nor restore_command is given.

Regards,

--
Fujii Masao
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center