Re: time-delayed standbys

On Thu, Jun 30, 2011 at 2:56 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> 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.

How is that different to running out of space in the main database?

If I try to pour a pint of milk into a small cup, I don't blame the cup.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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