[Python-Dev] Documentation about Python's GC, python-dev list messages referenced in Modules/gcmodule.c not reachable anymore

[Josiah Carlson]

Tim Peters <tim.peters at gmail.com> wrote:
> > ...
> 
> > In a specific program, analysis is much brighter. You *know* what
> > variables carry references to huge data structures, and you *know*
> > where these variables are assigned to.
> 
> > ...
> 
> Most people work with countless lines of library code they didn't
> write, and whose internals aren't documented at all.  When I do
> 
>     myinstance.a = zope.app.frobulater.gringo()
> 
> did I just create a reference to a huge new data structure?  I have no
> idea.  How long will refcounting take to clean up mysinstance.a when
> myinstance becomes trash?  Ditto.  Multiply by many thousands.  "Lazy"
> refcounting guarantees "not long" regardless -- although it introduces
> other problems.

I believe this particular argument is specious.  Using Python won't
change requirements for knowing what is or is not referenced during
program execution for "real time" development.  Further, "real time"
developers won't be using arbitrary 3rd party code which may do unknown
crazy things, it'll all be known crazy things.

My flight-controller-software-validator friend tells me that they use a
slimmed-down variant of Python for some of their software, and that it
works great.

 - Josiah