Subj : Re: why one stack per thread and one heap for multithread?
To   : comp.compilers.lcc,comp.programming.threads
From : Eric Sosman
Date : Fri Feb 25 2005 11:41 am



TonY wrote:
> Hi, 
> 
> why in multithreading, each thread has its own stack, but all share
> the same heap?
> I understand that one stack is needed for each thread as each could
> have its own procedure call. but why we don't associate a heap for
> each thread since each thread can also create dynamically its own
> data?

    Thread T1 (producer):

	ptr = malloc(sizeof *ptr);
	ptr->data = ...;
	add_to_shared_queue(ptr);

    Thread T2 (consumer):

	ptr = take_from_shared_queue();
	do_stuff_with(ptr->data);
	free(ptr);  /* Oops!  Not from my heap! */

-- 
Eric.Sosman@sun.com

.