interpreter crashes

[Peter Hansen]

Paul Rubin wrote:
> 
> Peter Hansen <peter at engcorp.com> writes:
> > Python can run indefinitely unless you have hit some obscure bug.  
> 
> This is encouraging to hear.  However, obscure bugs do exist.  I may
> be hitting a bug in some extension module or in something having to do
> with module reloading.

All crashes I've ever seen were with other libraries, or when
I was trying to wrap a DLL with calldll under Windows.  Never 
seen a crash yet under Linux.  Python is _solid_.

> > We are also developing applications based on Python which will
> > be expected to run potentially for years without being shut down ...
> > and I have no concerns about this (at least none related to Python! ;-).
> 
> This is my concern--if they're EXPECTED to run for years without
> shutdown, but they crash unexpectedly instead, that can be a big
> problem.  Best is to not have them crash, but next-best is to plan
> ahead for occasional crashes.  So I'm wondering what I need to do.

Run a separate task which checks the status of the Python app from
time to time (maybe with cron?).  Kill and restart as necessary.

> Note that if you're planning to run a server for years without
> attention, besides UPS's you'll also want to have some kind of
> hardware watchdog timer on the hosting computer--another form of crash
> tolerance.

Thanks for the advice :-).  It's an embedded PC104 module with
a hardware watchdog timer (they mostly all have them) and a 
stripped Linux platform, and the decision to use a UPS or not 
is the customer's, not ours. :-)

-- 
----------------------
Peter Hansen, P.Eng.
peter at engcorp.com