Re: remove wal_level archive

On Mon, Nov 2, 2015 at 2:21 PM, Craig Ringer <craig(at)2ndquadrant(dot)com> wrote:
> On 1 September 2015 at 10:39, Peter Eisentraut <peter_e(at)gmx(dot)net> wrote:
>> So we've had several rounds of discussions about simplifying replication
>> configuration in general and the wal_level setting in particular. [0][1]
>>
>> [snip]
>>
>> Bike-shedding: In this patch, I removed "archive" and kept
>> "hot_standby", because that's what the previous discussions suggested.
>> Historically and semantically, it would be more correct the other way
>> around. On the other hand, keeping "hot_standby" would probably require
>> fewer configuration files to be changed. Or we could keep both, but
>> that would be confusing (for users and in the code).
>
> We need to keep both, IMO, with 'archive' as an obsolete synonym for
> hot_standby.
>
> Otherwise pg_upgrade will get grumpy, and so will users who migrate
> their configurations.

pg_upgradecluster has some logic to switch a parameter value (see
strrepl), and pg_upgrade does not handle parameter name switches by
itself, so the price to pay would be more maintenance annoyance for
existing upgrade scripts, which happens at more or less each major
release (checkpoint_segments removed in 9.5, unix_socket_directory
renamed in 9.3, etc.).
--
Michael