Re: s6-rc user experience question

["Laurent Bercot" <ska-supervision@skarnet.org>]

>Perhaps I can offer a few suggestions how to improve usability:
>  - combine compile + svscan on empty dir + init steps into one, like
>    `s6-rc init source_dir` and it does those steps under the hood.

  No, because these are operations that are ideally done at different
times.
  - Compilation happens "offline", before you (re)boot the machine.
  - s6-svscan is run independently from s6-rc, typically very early
during the boot sequence. (Ideally it's process 1.) In any case the
preexistence of a supervision tree is assumed by s6-rc, so spawning
one as part of an s6-rc command isn't good workflow.
  - Initialization happens when the service manager is ready to run,
which means when the machine is online and already has an s6-svscan
running.

  Combining these operations is only useful if you're doing things in
a very convoluted, suboptimal way.


>  - maybe instead of creating file based database take on sqlite as a    dependency and keep compiled + live state there? sqlite is
>    ubiquitous and very light weight. It can save the trouble of
>    inventing our own compiled database formats and folder strucutres

  The format of the compiled database is entirely orthogonal to the
usability. Adding a dependency to an external package would do exactly
nothing to improve the UX here; it would just make the code bigger,
slower, more complex, harder to maintain and less secure. And that's
without mentioning that a relational database is not at all the right
structure for the kind of data that s6-rc deals with.

  Not a great trade-off, if you ask me.

  However, there's a change I can make that would immediately improve
s6-rc's usability: since it's largely a perception issue, changing
the vocabulary from "s6-rc-compile" to "s6-rc-snapshot" and
"compiled database" to "opaque snapshot of the set of services" would
be a good idea. It would spook fewer people, and send fewer people
into red herring trains of thoughts. :)


>What are your plans / thoughts on s6-rc redesign?

  It's ongoing. It's difficult, and I always find a myriad of things to
do to distract me from working on it, so it's going (very) slowly. But
it's always lurking in the back of my mind, and there isn't a day that
I don't wonder what I have gotten myself into.

  The initial call for funds is still readable here:
  https://skarnet.com/projects/service-manager.html

--
  Laurent