> > Perhaps a 'garbage collection' activity that reclaims stack > > pages from processes that have been asleep 'for a while' or > > haven't used a lot of stack recently (if hw 'page accessed' > > bit can be used) might make more sense. Interesting approach: if we take the original Andy's suggestion of using an access bit to know which stack pages were never used during context switch and unmap them, and as an extra optimization have a "garbage collector" that unmaps stacks in some long sleeping rarely used threads. I will think about this. Thanks, Pasha
