Re: postgresql.auto.conf read from wrong directory

On Thu, May 8, 2014 at 9:47 PM, Christoph Berg <cb(at)df7cb(dot)de> wrote:
> Re: Andres Freund 2014-05-08 <20140508145901(dot)GB1703(at)awork2(dot)anarazel(dot)de>
>> > Maybe this is nitpicking, but what happens when postgresql.auto.conf also
>> > includes the setting of data_directory? This is possible because we can
>> > set data_directory via ALTER SYSTEM now. Should we just ignore such
>> > problematic setting in postgresql.auto.conf with warning message?
>>
>> I think that's a case of "Doctor, it hurts when I do this. Doctor: don't
>> do that then".
>
> I'd opt to forbid setting data_directory at ALTER SYSTEM time. For the
> other options, I agree with Andres that you should get to keep all
> parts if you manage to break it.

There is no harm in forbidding data_directory, but similarly we can
imagine that people can set some very large values for some config
variables due to which later it can have symptoms similar to this
issue.

> Fortunately, ALTER SYSTEM already refuses to change config_file :)

That is because config_file is not a file parameter (not present in
postgresql.conf). We disallow non-file and internal (like wal_segment_size)
parameters in Alter System

With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com