On Oct 27, 2006, at 2:09 PM, Bill Schwab wrote:

> Making a long story short, I managed to hang Morphic in a big way, and
> needed a tool to debug it.  I approached it with a variant of a  
> trick I
> use in Dolphin, specifically for deployed executables, where I hook
> control-break to export call stacks on all non-dead threads.   
> Squeak is
> different because the VM is (in my experience at least) interactive  
> even
> if Morphic hangs.  Dolphin deployed executables will hang if

The way to do this in Squeak without hacking the VM is to run it  
under gdb, trigger the slow redraw, then interrupt it from gdb. Then  
you can print the stack for all active threads with "call (int)  
printAllStacks()".

Admittedly though, this is a pretty inconvenient technique to use on  
something that's not easily reproducible. I find that with the  
debugger fix from 3.9, I can go weeks without encountering a slow  
redraw.

Colin