Re: Completely new idea to virtual memory

[Chuck Ebbert]

>> Why not also write pages out to swap before it's really necessary?
>> If they were left mapped but marked as having up-to-date copies
>> on swap, they could be discarded immediately if the system needed
>> memory.  (Of course if they got written to they would have to be
>> paged out again.)
>
>Hmmm, interesting...

  The gains from this might be largely illusion but you could get some
theoretical benefits:

  o could write out lots of pages to swap without having to flush TLBs
    like you would if doing normal swap, since page remains present

  o if swsusp does not need to write already-backed pages it could
    reduce suspend time

  Maybe something like this?

   if about_to_spin_down_disks || swap_disk_idle
       if lots_of_memory_free
           page_in
       if little_memory_free
           copy_pages_to_swap
                  
 
--
 "Let's fight till six, and then have dinner," said Tweedledum.
  --Lewis Carroll, _Through the Looking Glass_