Re: 2.1.76, nfs client, and memory fragmentation

kwrohrer@enteract.com
Thu, 1 Jan 1998 18:19:20 -0600 (CST)


And lo, Alan Cox saith unto me:
> > > No, no reverse page tables. The data structures to keep them up-to-date
> > > worries me (it would essentially involve doubling all the page tables).
> >
> > One word: Eh?
> >
> > Based on what I did with Nachos it would take only one page table entry *
> > per page of physical memory; (alternately, the order-0 free bitmap [cw]ould
> How do you handle shared pages - you need more than one pointer in this case.
Presumably the same way they're already handled, if it's even that hard...
so long as we keep the right info. If you only denote shared pages in
core by a nonzero reference count, I could have a problem; looking at
vmalloc.c I don't see any handling of even a reference count so far, but
I haven't finished wading through the profusion of TLA's yet.

Keith