Re: AutoVacuum on demand?

On Nov 13, 2006, at 1:05 PM, Glen Parker wrote:

> Matthew T. O'Connor wrote:
>> Glen Parker wrote:
>>> I would like a way to run the autovacuum daemon on demand
>>> periodically.   Every night at 2 AM, for example.
>>>
>>> Anybody know if this is possible?  If not, it's a feature
>>> request :-)
>> Autovacuum can be enabled / disabled on the fly using the GUC
>> settings.  Perhaps you can write a cron script that runs at 2AM
>> that enables autovac, and at 6AM (just a guess) disables it in the
>> same fashion.  I think that should work.
>> Would be curious to hear your results.
>
> I thought it sounded like a good idea, but then...
>
> SET autovacuum = on;
> ERROR:  parameter "autovacuum" cannot be changed now

I've turned it on and off in the postgresql.conf several times
(followed by a postmaster HUP) and it worked as expected. I think
this is a global setting that cannot be toggled in a particular session.

-Casey