[Openmcl-devel] My beach balls runneth over

Gary Byers gb at clozure.com
Tue May 19 13:36:32 PDT 2009

Without a reliable way to reproduce the problem(s), it's very difficult
to have any idea of what the problem is or how to fix it.

If you wind up in the kernel debugger and don't know why, trying to
figure out how you got there ("b" generates a backtrace that at least
shows the lisp stack up to the last foreign function call, "r" shows
machine register values.  If running under the standlone IDE, output
from those commands goes to the window maintained by the AltConsole
application; that windows's contents can be saved to a text file.

Many library functions write diagnostic messages to system logfiles;
/Applications/Utilities/Console.app can be used to view these logfiles.
It's possible that some messages might mention problems that lead up
to the SBOD.

The beachball cursor generally means that the thread which waits for
and processes events hasn't tried to fetch an event in a while (I
think that "a while" is "about 1 second.")  There can be any number
of reasons for this; among the more mundane reasons are cases where
the event thread is sitting in the kernel debugger or a break loop
(waiting for input in the AltConsole window.)

On Tue, 19 May 2009, Ron Garret wrote:

> I regret to report that CCL 1.3 seems to still have some pretty
> serious bugs.  The UI is much improved, pretty much usable at this
> point.  But as soon as I lean on it (i.e. try to run some of Alexander
> Repenning's demos) it hangs  with the dreaded SBOD.  Sometimes it
> hangs without my even having to lean on it, just playing around with
> Hemlock (and by "playing around" I mean just editing, not hacking the
> Hemlock code).  On one occasion I ended up in the CCL Kernel
> debugger.  I have not yet played around enough to see if I can find a
> reliable way to reproduce the problem.  Many of the demos do work, but
> I have yet to go more than about 10 minutes at a time without a crash.
> My questions are:
> 1.  Is anyone else seeing this behavior or is it just me?  I can't
> imagine how Alexander was able to write this code if he was having the
> same experience I am.
> 2.  If this is a known problem, what's the prognosis for getting it
> fixed?
> 3.  Is there anything I can do when I encounter the SBOD to extract
> useful debugging information?
> Thanks,
> rg
> _______________________________________________
> Openmcl-devel mailing list
> Openmcl-devel at clozure.com
> http://clozure.com/mailman/listinfo/openmcl-devel

More information about the Openmcl-devel mailing list