Re: [HACKERS] [PATCH] A hook for session start

Michael Paquier <michael.paquier@gmail.com> writes:
> I was the one suggesting to Fabrizio to look at how backend types are
> evaluated in pgstat.c after an off-list discussion. Agreed that this
> result is fragile as this makes two places dependent on the process
> types. Why not simply moving all the business of pgstat_bestart()
> evaluating which st_backendType to use into a common routine and have
> pgstat.c and have this utility use this API? pgstat.h already includes
> BackendType as an enum to use so this could live with a routine
> available in pgstat.c. Or would it be cleaner to have a new thing
> dedicated to process-related information, say as
> src/backend/utils/misc/process_info.c? It is indeed strange to have a
> session-related feature depend on something with statistics.

This is really about consolidating a whole bunch of ad-hoc stuff.
I don't think pgstat has any particular pride of place here.  It
should be one consumer of a common API.

The stuff related to AuxProcType is in miscadmin.h, so one possibility
is to put the new enum there.  But I could see inventing a whole new
header for this, "utils/proctype.h" or so.
        regards, tom lane