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

@@ -764,11 +764,10 @@
         segmf_fault,
         segmf_faulta,
         segmf_setprot,
         segmf_checkprot,
         (int (*)())segmf_kluster,
-        (size_t (*)(struct seg *))NULL, /* swapout */
         segmf_sync,
         segmf_incore,
         segmf_lockop,
         segmf_getprot,
         segmf_getoffset,