Re: time-delayed standbys

On Wed, Jun 29, 2011 at 9:54 PM, Josh Berkus <josh(at)agliodbs(dot)com> wrote:
>> I am not sure exactly how walreceiver handles it if the disk is full.
>> I assume it craps out and eventually retries, so probably what will
>> happen is that, after the standby's pg_xlog directory fills up,
>> walreceiver will sit there and error out until replay advances enough
>> to remove a WAL file and thus permit some more data to be streamed.
>
> Nope, it gets stuck and stops there.  Replay doesn't advance unless you
> can somehow clear out some space manually; if the disk is full, the disk
> is full, and PostgreSQL doesn't remove WAL files without being able to
> write files first.
>
> Manual (or scripted) intervention is always necessary if you reach disk
> 100% full.

Wow, that's a pretty crappy failure mode... but I don't think we need
to fix it just on account of this patch. It would be nice to fix, of
course.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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