Re: [DOC] Add detail regarding resource consumption wrt max_connections

On Fri, 2024-01-19 at 17:37 -0500, reid(dot)thompson(at)crunchydata(dot)com wrote:
> On Sat, 2024-01-13 at 10:31 -0700, Roberto Mello wrote:
> >
> > I can add a suggestion for the user to consider increasing
> > shared_buffers in accordance with higher max_connections, but it
> > would be better if there was a "rule of thumb" guideline to go
> > along. I'm open to suggestions.
> >
> > I can revise with a similar warning in max_prepared_xacts as well.
> >
> > Sincerely,
> >
> > Roberto
>
> Can a "close enough" rule of thumb be calculated from:
> postgresql.conf -> log_min_messages = debug3
>
> start postgresql with varying max_connections to get
> CreateSharedMemoryAndSemaphores() sizes to generate a rough equation
>

or maybe it would be sufficient to advise to set log_min_messages =
debug3 on a test DB and start/stop it with varying values of
max_connections and look at the differing values in
DEBUG: invoking IpcMemoryCreate(size=...) log messages for themselves.