Index: sys/proc.h
===================================================================
RCS file: /cvs/src/sys/sys/proc.h,v
diff -u -p -r1.376 proc.h
--- sys/proc.h	22 Oct 2024 11:54:05 -0000	1.376
+++ sys/proc.h	8 Dec 2024 12:09:11 -0000
@@ -95,11 +95,20 @@ struct	pgrp {
  * generation counter. Code should use tu_enter() and tu_leave() for this.
  * The process ps_tu structure is locked by the ps_mtx.
  */
+#define TU_UTICKS	0		/* Statclock hits in user mode. */
+#define TU_STICKS	1		/* Statclock hits in system mode. */
+#define TU_ITICKS	2		/* Statclock hits processing intr. */
+#define TU_TICKS_COUNT	3
+
 struct tusage {
 	uint64_t	tu_gen;		/* generation counter */
-	uint64_t	tu_uticks;	/* Statclock hits in user mode. */
-	uint64_t	tu_sticks;	/* Statclock hits in system mode. */
-	uint64_t	tu_iticks;	/* Statclock hits processing intr. */
+	uint64_t	tu_ticks[TU_TICKS_COUNT];
+#define tu_uticks	tu_ticks[TU_UTICKS]
+#define tu_sticks	tu_ticks[TU_STICKS]
+#define tu_iticks	tu_ticks[TU_ITICKS]
+	uint64_t	tu_ixrss;
+	uint64_t	tu_idrss;
+	uint64_t	tu_isrss;
 	struct	timespec tu_runtime;	/* Realtime. */
 };
 
Index: kern/kern_clock.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_clock.c,v
diff -u -p -r1.124 kern_clock.c
--- kern/kern_clock.c	8 Jul 2024 13:17:11 -0000	1.124
+++ kern/kern_clock.c	8 Dec 2024 12:09:11 -0000
@@ -49,6 +49,7 @@
 #include <sys/sysctl.h>
 #include <sys/sched.h>
 #include <sys/timetc.h>
+#include <uvm/uvm_extern.h>
 
 /*
  * Clock handling routines.
@@ -267,6 +268,8 @@ statclock(struct clockrequest *cr, void 
 	struct schedstate_percpu *spc = &ci->ci_schedstate;
 	struct proc *p = curproc;
 	struct process *pr;
+	int tu_tick = -1;
+	int cp_time;
 
 	if (statclock_is_randomized) {
 		count = clockrequest_advance_random(cr, statclock_min,
@@ -281,13 +284,8 @@ statclock(struct clockrequest *cr, void 
 		 * Came from user mode; CPU was in user state.
 		 * If this process is being profiled record the tick.
 		 */
-		tu_enter(&p->p_tu);
-		p->p_tu.tu_uticks += count;
-		tu_leave(&p->p_tu);
-		if (pr->ps_nice > NZERO)
-			spc->spc_cp_time[CP_NICE] += count;
-		else
-			spc->spc_cp_time[CP_USER] += count;
+		tu_tick = TU_UTICKS;
+		cp_time = (pr->ps_nice > NZERO) ? CP_NICE : CP_USER;
 	} else {
 		/*
 		 * Came from kernel mode, so we were:
@@ -303,26 +301,39 @@ statclock(struct clockrequest *cr, void 
 		 * in ``non-process'' (i.e., interrupt) work.
 		 */
 		if (CLKF_INTR(frame)) {
-			if (p != NULL) {
-				tu_enter(&p->p_tu);
-				p->p_tu.tu_iticks += count;
-				tu_leave(&p->p_tu);
-			}
-			spc->spc_cp_time[spc->spc_spinning ?
-			    CP_SPIN : CP_INTR] += count;
+			tu_tick = TU_ITICKS;
+			cp_time = CP_INTR;
 		} else if (p != NULL && p != spc->spc_idleproc) {
-			tu_enter(&p->p_tu);
-			p->p_tu.tu_sticks += count;
-			tu_leave(&p->p_tu);
-			spc->spc_cp_time[spc->spc_spinning ?
-			    CP_SPIN : CP_SYS] += count;
+			tu_tick = TU_STICKS;
+			cp_time = CP_SYS;
 		} else
-			spc->spc_cp_time[spc->spc_spinning ?
-			    CP_SPIN : CP_IDLE] += count;
+			cp_time = CP_IDLE;
+
+		if (spc->spc_spinning)
+			cp_time = CP_SPIN;
 	}
 
+	spc->spc_cp_time[cp_time] += count;
+
 	if (p != NULL) {
 		p->p_cpticks += count;
+
+		if (!ISSET(p->p_flag, P_SYSTEM) && tu_tick != -1) {
+			struct vmspace *vm = p->p_vmspace;
+			struct tusage *tu = &p->p_tu;
+
+			tu_enter(tu);
+			tu->tu_ticks[tu_tick] += count;
+
+			/* maxrss is handled by uvm */
+			if (tu_tick != TU_ITICKS) {
+				tu->tu_ixrss += (vm->vm_tsize << (PAGE_SHIFT - 10)) * count;
+				tu->tu_idrss += (vm->vm_dused << (PAGE_SHIFT - 10)) * count;
+				tu->tu_isrss += (vm->vm_ssize << (PAGE_SHIFT - 10)) * count;
+			}
+			tu_leave(tu);
+		}
+
 		/*
 		 * schedclock() runs every fourth statclock().
 		 */
Index: kern/kern_exit.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_exit.c,v
diff -u -p -r1.239 kern_exit.c
--- kern/kern_exit.c	15 Oct 2024 13:49:26 -0000	1.239
+++ kern/kern_exit.c	8 Dec 2024 12:09:11 -0000
@@ -346,6 +346,9 @@ exit1(struct proc *p, int xexit, int xsi
 		 * and calculate the total times.
 		 */
 		calcru(&pr->ps_tu, &rup->ru_utime, &rup->ru_stime, NULL);
+		rup->ru_ixrss = pr->ps_tu.tu_ixrss;
+		rup->ru_idrss = pr->ps_tu.tu_idrss;
+		rup->ru_isrss = pr->ps_tu.tu_isrss;
 		ruadd(rup, &pr->ps_cru);
 
 		/*
Index: kern/kern_resource.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_resource.c,v
diff -u -p -r1.93 kern_resource.c
--- kern/kern_resource.c	10 Nov 2024 06:45:36 -0000	1.93
+++ kern/kern_resource.c	8 Dec 2024 12:09:11 -0000
@@ -395,6 +395,9 @@ tuagg_sumup(struct tusage *tu, const str
 	tu->tu_uticks += tmp.tu_uticks;
 	tu->tu_sticks += tmp.tu_sticks;
 	tu->tu_iticks += tmp.tu_iticks;
+	tu->tu_ixrss += tmp.tu_ixrss;
+	tu->tu_idrss += tmp.tu_idrss;
+	tu->tu_isrss += tmp.tu_isrss;
 	timespecadd(&tu->tu_runtime, &tmp.tu_runtime, &tu->tu_runtime);
 }
 
@@ -440,6 +443,7 @@ tuagg_add_process(struct process *pr, st
 	/* Now reset CPU time usage for the thread. */
 	timespecclear(&p->p_tu.tu_runtime);
 	p->p_tu.tu_uticks = p->p_tu.tu_sticks = p->p_tu.tu_iticks = 0;
+	p->p_tu.tu_ixrss = p->p_tu.tu_idrss = p->p_tu.tu_isrss = 0;
 }
 
 void
@@ -567,6 +571,10 @@ dogetrusage(struct proc *p, int who, str
 		}
 
 		calcru(&tu, &rup->ru_utime, &rup->ru_stime, NULL);
+
+		rup->ru_ixrss = tu.tu_ixrss;
+		rup->ru_idrss = tu.tu_idrss;
+		rup->ru_isrss = tu.tu_isrss;
 		break;
 
 	case RUSAGE_THREAD: