On Sat, 19 Apr 1997, Colin Wood wrote:

> Just in case anyone was wondering what actually does happen when you have
> a machine that has no swap and it runs out of physical memory, here's the
> answer:
> 
> it hangs.
> 
> That simple.  Everything is going along perfectly fine, and then it hangs.
> A trace in the debugger shows that it hangs a few calls down into the vm
> code, which is what I would pretty much expect.
> 
> I hope that somewhat answers someone's question about running out of swap
> earlier.

My original question was more precisely: what happens when you do have 
some swap but it runs out of that too? I guess running without any swap 
is a very unlikely configuration and certainly not recommended but 
assuming that running out of swap space has the same effect as running 
out of memory when you dont have swap, it doesn't matter.

Thanks for the answer, it is pretty much what I wanted to know unless 
there's a special trick to handle out-of-mem better when using swap but 
my guess is there isn't. I hope to be able to verify that when I know 
enough to read the vm code and make sense of it. Again, thanks.

> 
> Later.
> 
> -- 
> Colin Wood                                      ender@is.rice.edu
> Consultant                                        Rice University
> Information Technology Services                       Houston, TX
> 
> P.S.  I've just set up an SE/30 with 8 MB RAM and an 80 MB harddrive and
> haven't set up the swap partition yet (the MacOS partition that currently
> holds the system will have to go first ;-)
> 

-----------------------------------------------------------------
"Because user errors often produce unpredictable results, the user
should try to avoid them."

IBM MVS/XA System Programming Library.