Re: Support for pg_receivexlog --post-segment command

Feike Steenbergen <feikesteenbergen@gmail.com>

From: Feike Steenbergen <feikesteenbergen@gmail.com>
To: Magnus Hagander <magnus@hagander.net>
Cc: David Steele <david@pgmasters.net>, PostgreSQL mailing lists <pgsql-hackers@postgresql.org>
Date: 2017-01-06T13:49:37Z
Lists: pgsql-hackers
On Fri, Jan 6, 2017 at 2:30 PM, David Steele <david@pgmasters.net> wrote:
> For my part I still prefer an actual command to be executed so it will
start/restart the archiver if it is not already running or died.  This
reduces the number of processes that I need to ensure are running.
>
> If the consensus is that a signal is better then I'll make that work.  I
will say this raises the bar on what is required to write a good archive
command and we already know it is quite a difficult task.

On 6 January 2017 at 14:37, Magnus Hagander <magnus@hagander.net> wrote:
> I like the idea of a command as well, for flexibility. If you want a
signal, you can write a trivial command that sends the signal... Maximum
flexibility, as long as we don't create a lot of caveats for users.

Agreed, I think it is also easier to understand the mechanism (instead of a
signal), and would allow for some reuse of already existing scripts.

If we do use a full command (vs a signal), I propose we do also offer the
%p and %f placeholders for the command.