--- vm_page.c	2010-09-03 12:40:53.000000000 +0200
+++ vm_page.c.stats	2010-09-24 17:53:28.000000000 +0200
@@ -113,6 +113,7 @@
 #include <sys/mutex.h>
 #include <sys/proc.h>
 #include <sys/sysctl.h>
+#include <sys/types.h>
 #include <sys/vmmeter.h>
 #include <sys/vnode.h>
 
@@ -131,6 +132,7 @@
 #include <vm/uma_int.h>
 
 #include <machine/md_var.h>
+#include <machine/atomic.h>
 
 #if defined(__amd64__) || defined (__i386__) 
 extern struct sysctl_oid_list sysctl__vm_pmap_children;
@@ -150,6 +152,29 @@
 SYSCTL_INT(_vm_pmap, OID_AUTO, tryrelock_race, CTLFLAG_RD,
     &pmap_tryrelock_race, 0, "Number of tryrelock pmap race cases");
 
+static int vmpage_splay_lookup = 0;
+static int vmpage_splay_cachehit = 0;
+static int vmpage_splay_rotate = 0;
+static int vmpage_splay_rotatetouch = 0;
+static int vmpage_splay_insert = 0;
+static int vmpage_splay_remove = 0;
+
+SYSCTL_NODE(_vm, OID_AUTO, page, CTLFLAG_RD, 0, "VM/page statistics");
+SYSCTL_INT(_vm_pmap, OID_AUTO, vmpage_splay_lookup, CTLFLAG_RD,
+    &vmpage_splay_lookup, 0, "");
+SYSCTL_INT(_vm_pmap, OID_AUTO, vmpage_splay_cachehit, CTLFLAG_RD,
+    &vmpage_splay_cachehit, 0, "");
+SYSCTL_INT(_vm_pmap, OID_AUTO, vmpage_splay_rotate, CTLFLAG_RD,
+    &vmpage_splay_rotate, 0, "");
+SYSCTL_INT(_vm_pmap, OID_AUTO, vmpage_splay_rotatetouch, CTLFLAG_RD,
+    &vmpage_splay_rotatetouch, 0, "");
+SYSCTL_INT(_vm_pmap, OID_AUTO, vmpage_splay_insert, CTLFLAG_RD,
+    &vmpage_splay_insert, 0, "");
+SYSCTL_INT(_vm_pmap, OID_AUTO, vmpage_splay_remove, CTLFLAG_RD,
+    &vmpage_splay_remove, 0, "");
+
+#define	PAGESTAT(x)	atomic_add_int(&(x), 1)
+
 /*
  *	Associated with page of user-allocatable memory is a
  *	page structure.
@@ -686,6 +711,9 @@
 	if (root == NULL)
 		return (root);
 	lefttreemax = righttreemin = &dummy;
+
+	PAGESTAT(vmpage_splay_rotate);
+
 	for (;; root = y) {
 		if (pindex < root->pindex) {
 			if ((y = root->left) == NULL)
@@ -717,6 +745,7 @@
 			lefttreemax = root;
 		} else
 			break;
+		PAGESTAT(vmpage_splay_rotatetouch);
 	}
 	/* Assemble the new root. */
 	lefttreemax->right = root->left;
@@ -754,6 +783,8 @@
 	m->object = object;
 	m->pindex = pindex;
 
+	PAGESTAT(vmpage_splay_insert);
+
 	/*
 	 * Now link into the object's ordered list of backed pages.
 	 */
@@ -827,6 +858,8 @@
 		vm_page_flash(m);
 	}
 
+	PAGESTAT(vmpage_splay_remove);
+
 	/*
 	 * Now remove from the object's list of backed pages.
 	 */
@@ -871,11 +904,16 @@
 	vm_page_t m;
 
 	VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
+
+	PAGESTAT(vmpage_splay_lookup);
+
 	if ((m = object->root) != NULL && m->pindex != pindex) {
 		m = vm_page_splay(pindex, m);
 		if ((object->root = m)->pindex != pindex)
 			m = NULL;
-	}
+	} else if (m != NULL)
+		PAGESTAT(vmpage_splay_cachehit);
+
 	return (m);
 }
 
@@ -894,6 +932,9 @@
 	vm_page_t m;
 
 	VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
+
+	PAGESTAT(vmpage_splay_lookup);
+
 	if ((m = TAILQ_FIRST(&object->memq)) != NULL) {
 		if (m->pindex < pindex) {
 			m = vm_page_splay(pindex, object->root);
@@ -1051,7 +1092,8 @@
 		m = vm_page_splay(pindex, m);
 		if ((object->cache = m)->pindex != pindex)
 			m = NULL;
-	}
+	} else if (m != NULL)
+		PAGESTAT(vmpage_splay_cachehit);
 	return (m);
 }
 
@@ -1071,6 +1113,9 @@
 	KASSERT((m->flags & PG_CACHED) != 0,
 	    ("vm_page_cache_remove: page %p is not cached", m));
 	object = m->object;
+
+	PAGESTAT(vmpage_splay_remove);
+
 	if (m != object->cache) {
 		root = vm_page_splay(m->pindex, object->cache);
 		KASSERT(root == m,
--- vm_map.c	2010-09-19 19:43:22.000000000 +0200
+++ vm_map.c.stats	2010-09-30 18:10:35.000000000 +0200
@@ -67,17 +67,21 @@
 
 #include <sys/param.h>
 #include <sys/systm.h>
+#include <sys/file.h>
 #include <sys/ktr.h>
 #include <sys/lock.h>
+#include <sys/kernel.h>
+#include <sys/limits.h>
+#include <sys/mman.h>
 #include <sys/mutex.h>
 #include <sys/proc.h>
-#include <sys/vmmeter.h>
-#include <sys/mman.h>
-#include <sys/vnode.h>
 #include <sys/resourcevar.h>
-#include <sys/file.h>
 #include <sys/sysent.h>
 #include <sys/shm.h>
+#include <sys/sysctl.h>
+#include <sys/types.h>
+#include <sys/vmmeter.h>
+#include <sys/vnode.h>
 
 #include <vm/vm.h>
 #include <vm/vm_param.h>
@@ -91,6 +95,32 @@
 #include <vm/swap_pager.h>
 #include <vm/uma.h>
 
+#include <machine/atomic.h>
+
+static int vmmap_splay_lookup = 0;
+static int vmmap_splay_cachehit = 0;
+static int vmmap_splay_rotate = 0;
+static int vmmap_splay_rotatetouch = 0;
+static int vmmap_splay_insert = 0;
+static int vmmap_splay_remove = 0;
+
+static SYSCTL_NODE(_vm, OID_AUTO, map, CTLFLAG_RD, 0, "VM/map statistics");
+
+SYSCTL_INT(_vm_map, OID_AUTO, vmmap_splay_lookup, CTLFLAG_RD,
+    &vmmap_splay_lookup, 0, "");
+SYSCTL_INT(_vm_map, OID_AUTO, vmmap_splay_cachehit, CTLFLAG_RD,
+    &vmmap_splay_cachehit, 0, "");
+SYSCTL_INT(_vm_map, OID_AUTO, vmmap_splay_rotate, CTLFLAG_RD,
+    &vmmap_splay_rotate, 0, "");
+SYSCTL_INT(_vm_map, OID_AUTO, vmmap_splay_rotatetouch, CTLFLAG_RD,
+    &vmmap_splay_rotatetouch, 0, "");
+SYSCTL_INT(_vm_map, OID_AUTO, vmmap_splay_insert, CTLFLAG_RD,
+    &vmmap_splay_insert, 0, "");
+SYSCTL_INT(_vm_map, OID_AUTO, vmmap_splay_remove, CTLFLAG_RD,
+    &vmmap_splay_remove, 0, "");
+
+#define MAPSTAT(x)     atomic_add_int(&(x), 1)
+
 /*
  *	Virtual memory maps provide for the mapping, protection,
  *	and sharing of virtual memory objects.  In addition,
@@ -819,6 +849,8 @@
 	if (root == NULL)
 		return (root);
 
+	MAPSTAT(vmmap_splay_rotate);
+
 	/*
 	 * Pass One: Splay down the tree until we find addr or a NULL
 	 * pointer where addr would go.  llist and rlist are the two
@@ -869,6 +901,7 @@
 			}
 		} else
 			break;
+		MAPSTAT(vmmap_splay_rotatetouch);
 	}
 
 	/*
@@ -924,6 +957,8 @@
 	entry->next->prev = entry;
 	after_where->next = entry;
 
+	MAPSTAT(vmmap_splay_insert);
+
 	if (after_where != &map->header) {
 		if (after_where != map->root)
 			vm_map_entry_splay(after_where->start, map->root);
@@ -933,6 +968,7 @@
 		after_where->adj_free = entry->start - after_where->end;
 		vm_map_entry_set_max_free(after_where);
 	} else {
+		MAPSTAT(vmmap_splay_cachehit);
 		entry->right = map->root;
 		entry->left = NULL;
 	}
@@ -949,11 +985,15 @@
 	vm_map_entry_t next, prev, root;
 
 	VM_MAP_ASSERT_LOCKED(map);
+
+	MAPSTAT(vmmap_splay_remove);
+
 	if (entry != map->root)
 		vm_map_entry_splay(entry->start, map->root);
-	if (entry->left == NULL)
+	if (entry->left == NULL) {
+		MAPSTAT(vmmap_splay_cachehit);
 		root = entry->right;
-	else {
+	}else {
 		root = vm_map_entry_splay(entry->start, entry->left);
 		root->right = entry->right;
 		root->adj_free = (entry->next == &map->header ? map->max_offset :
@@ -1017,6 +1057,8 @@
 	vm_map_entry_t cur;
 	boolean_t locked;
 
+	MAPSTAT(vmmap_splay_lookup);
+
 	/*
 	 * If the map is empty, then the map entry immediately preceding
 	 * "address" is the map's header.
@@ -1025,6 +1067,7 @@
 	if (cur == NULL)
 		*entry = &map->header;
 	else if (address >= cur->start && cur->end > address) {
+		MAPSTAT(vmmap_splay_cachehit);
 		*entry = cur;
 		return (TRUE);
 	} else if ((locked = vm_map_locked(map)) ||