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

@@ -29,12 +29,10 @@
 /*
  * Portions of this source code were derived from Berkeley 4.3 BSD
  * under license from the Regents of the University of California.
  */
 
-#pragma ident   "%Z%%M% %I%     %E% SMI"
-
 /*
  * VM - segment for non-faulting loads.
  */
 
 #include <sys/types.h>

@@ -95,11 +93,10 @@
         (faultcode_t (*)(struct seg *, caddr_t))
                 segnf_nomap,            /* faulta */
         segnf_setprot,
         segnf_checkprot,
         (int (*)())segnf_badop,         /* kluster */
-        (size_t (*)(struct seg *))NULL, /* swapout */
         (int (*)(struct seg *, caddr_t, size_t, int, uint_t))
                 segnf_nop,              /* sync */
         (size_t (*)(struct seg *, caddr_t, size_t, char *))
                 segnf_nop,              /* incore */
         (int (*)(struct seg *, caddr_t, size_t, int, int, ulong_t *, size_t))