Re: when the startup process doesn't

On Tue, Apr 20, 2021 at 5:17 PM Jehan-Guillaume de Rorthais
<jgdr(at)dalibo(dot)com> wrote:
>
> On Tue, 20 Apr 2021 15:04:28 +0200
> Magnus Hagander <magnus(at)hagander(dot)net> wrote:
> [...]
> > Yeah, I think we should definitely limit this to local access, one way
> > or another. Realistically using pg_hba is going to require catalog
> > access, isn't it? And we can't just go ignore those rows in pg_hba
> > that for example references role membership (as well as all those auth
> > methods you can't use).
>
> Two another options:
>
> 1. if this is limited to local access only, outside of the log entries, the
> status of the startup could be updated in the controldata file as well. This
> would allows to watch it without tail-grep'ing logs using eg. pg_controldata.

I think doing so in controldata would definitely make things
complicated for no real reason. Plus controldata has a fixed size (and
has to have), whereas something like this would probably want more
variation than that makes easy.

There could be a "startup.status" file I guess which would basically
contain the last line of what would otherwise be in the log. But if it
remains a textfile, I'm not sure what the gain is -- you'll just have
to have the dba look in more places than one to find it? It's not like
there's likely to be much other data written to the log during these
times?

> 2. maybe the startup process could ignore update_process_title? As far
> as I understand the doc correctly, this GUC is mostly useful for backends on
> Windows.

You mention Windows -- that would be one excellent reason not to go
for this particular method. Viewing the process title is much harder
on Windows, as there is actually no such thing and we fake it.

--
Magnus Hagander
Me: https://www.hagander.net/
Work: https://www.redpill-linpro.com/