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

@@ -28,12 +28,10 @@
 
 
 #ifndef _SYS_DISP_H
 #define _SYS_DISP_H
 
-#pragma ident   "%Z%%M% %I%     %E% SMI"        /* SVr4.0 1.11  */
-
 #include <sys/priocntl.h>
 #include <sys/thread.h>
 #include <sys/class.h>
 
 #ifdef  __cplusplus

@@ -141,12 +139,10 @@
 extern void             setfrontdq(kthread_t *);
 extern void             swtch(void);
 extern void             swtch_to(kthread_t *);
 extern void             swtch_from_zombie(void)
                                 __NORETURN;
-extern void             dq_sruninc(kthread_t *);
-extern void             dq_srundec(kthread_t *);
 extern void             cpu_rechoose(kthread_t *);
 extern void             cpu_surrender(kthread_t *);
 extern void             kpreempt(int);
 extern struct cpu       *disp_lowpri_cpu(struct cpu *, struct lgrp_ld *, pri_t,
                             struct cpu *);