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

*** 437,448 ****
  extern int      anon_copy_ptr(struct anon_hdr *, ulong_t,
                      struct anon_hdr *, ulong_t, pgcnt_t, int);
  extern pgcnt_t  anon_grow(struct anon_hdr *, ulong_t *, pgcnt_t, pgcnt_t, int);
  extern void     anon_array_enter(struct anon_map *, ulong_t,
                          anon_sync_obj_t *);
- extern int      anon_array_try_enter(struct anon_map *, ulong_t,
-                         anon_sync_obj_t *);
  extern void     anon_array_exit(anon_sync_obj_t *);
  
  /*
   * anon_resv checks to see if there is enough swap space to fulfill a
   * request and if so, reserves the appropriate anonymous memory resources.
--- 437,446 ----