Re: enhance pg_log_backend_memory_contexts() to log memory contexts of auxiliary processes

On Mon, Oct 11, 2021 at 8:21 AM torikoshia <torikoshia(at)oss(dot)nttdata(dot)com> wrote:
>
> Thanks for working on this!
>
> On 2021-10-09 22:23, Bharath Rupireddy wrote:
> > Hi,
> >
> > Currently pg_log_backend_memory_contexts() doesn't log the memory
> > contexts of auxiliary processes such as bgwriter, checkpointer, wal
> > writer, archiver, startup process and wal receiver. It will be useful
> > to look at the memory contexts of these processes too, for debugging
> > purposes and better understanding of the memory usage pattern of these
> > processes.
>
> As the discussion below, we thought logging memory contexts of other
> than client backends is possible but were not sure how useful it is.
> After all, we have ended up restricting the target process to client
> backends for now.
>
>
> https://www.postgresql.org/message-id/0b0657d5febd0e46565a6bc9c62ba3f6%40oss.nttdata.com
>
> If we can use debuggers, it's possible to know the memory contexts e.g.
> using MemoryContextStats().
> So IMHO if it's necessary to know memory contexts without attaching gdb
> for other than client backends(probably this means using under
> production environment), this enhancement would be pay.

Thanks for providing your thoughts. Knowing memory usage of auxiliary
processes is as important as backends (user session processes) without
attaching debugger in production environments.

There are some open points as mentioned in my first mail in this
thread, I will start working on this patch once we agree on them.

Regards,
Bharath Rupireddy.