Nick Piggin <piggin@xxxxxxxxxxxxxxx> wrote:
Not too sure what you mean. If we've swapped out the pages, it is
because we need the memory for something else. So no.
Actually - no, from what Andrew said, the system was not under memory
pressure and did not need the memory for something else. The swapping
occurred "just because". In that case, it would be better to keep track
of where the pages came from (i.e., swap them in from the free list).
Don't get me wrong - that behavior may be the "right thing" from an
overall performance standpoint. A little extra disk I/O when the system
is relatively idle may provide needed reserve (free pages) for when the
system gets busy again.
One thing you could do is re read swapped pages when you haveThat may also be a good idea. However, if you keep a mapping between
plenty of free memory and the disks are idle.
pages on the "free list" and those in the swap file / partition, you
do not actually have to do the disk I/O to accomplish that.