Re: WAL segments pile up during standalone mode

On Thu, Mar 3, 2011 at 9:15 AM, Alvaro Herrera
<alvherre(at)commandprompt(dot)com> wrote:
> Excerpts from Fujii Masao's message of mié mar 02 22:44:45 -0300 2011:
>> On Thu, Mar 3, 2011 at 3:22 AM, Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> wrote:
>> > I noticed that in standalone mode, WAL segments don't seem to be
>> > recycled.  This could get problematic if you're forced to vacuum large
>> > tables in that mode and space for WAL is short.
>>
>> Checkpoint is required to recycle old WAL segments. Can checkpoint
>> be executed in standalone mode? even during VACUUM FULL?
>
> Hmm, I guess it would violate POLA that the standalone server would
> decide to run checkpoint in the middle of vacuum.  I imagine that in
> some cases the only option would be to process the tables manually, with
> the ALTER TABLE/SET TYPE trick or similar (VACUUM FULL in 9.0+).
>
> So I can see that there is no good fix for this problem, yet it is a
> very inconvenient situation to be in.

I don't think it would violate the POLA for a standalone backend to
checkpoint periodically, but I have to admit I can count the number of
times I've run a standalone backend on one hand. Does this come up
much?

--
Robert Haas
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