Re: background sessions

2017-01-03 19:39 GMT+05:00 Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)
com>:

> On 1/3/17 1:26 AM, amul sul wrote:
> > One more requirement for pg_background is session, command_qh,
> > response_qh and worker_handle should be last longer than current
> > memory context, for that we might need to allocate these in
> > TopMemoryContext. Please find attach patch does the same change in
> > BackgroundSessionStart().
>
> I had pondered this issue extensively. The standard coding convention
> in postgres is that the caller sets the memory context. See the dblink
> and plpython patches that make this happen in their own way.
>
> I agree it would make sense that you either pass in a memory context or
> always use TopMemoryContext. I'm open to these ideas, but they did not
> seem to match any existing usage.
>
+1
Please excuse me if I'm not getting something obvious, but seems like
BackgroundSessionNew() caller from pg_background_launch() can pick up
TopMemoryCtx. I think that context setup should be done by extension, not
by bg_session API.

Best regards, Andrey Borodin.