remove whole-process swapping
Long before Unix supported paging, it used process swapping to reclaim
memory.  The code is there and in theory it runs when we get *extremely* low
on memory.  In practice, it never runs since the definition of low-on-memory
is antiquated. (XXX: define what antiquated means)
You can check the number of swapout/swapin events with kstats:
$ kstat -p ::vm:swapin ::vm:swapout

@@ -198,11 +198,10 @@
         segdev_fault,
         segdev_faulta,
         segdev_setprot,
         segdev_checkprot,
         (int (*)())segdev_badop,        /* kluster */
-        (size_t (*)(struct seg *))NULL, /* swapout */
         segdev_sync,                    /* sync */
         segdev_incore,
         segdev_lockop,                  /* lockop */
         segdev_getprot,
         segdev_getoffset,