Index: sys/vm/vm_map.c
===================================================================
--- sys/vm/vm_map.c
+++ sys/vm/vm_map.c
@@ -917,36 +917,44 @@
 	entry->max_free = MAX(max_left, max_right);
 }
 
-#define SPLAY_LEFT_STEP(root, y, rlist, test) do {	\
-	y = root->left;					\
-	if (y != NULL && (test)) {			\
-		/* Rotate right and make y root. */	\
-		root->left = y->right;			\
-		y->right = root;			\
-		vm_map_entry_set_max_free(root);	\
-		root = y;				\
-		y = root->left;				\
-	}						\
-	/* Put root on rlist. */			\
-	root->left = rlist;				\
-	rlist = root;					\
-	root = y;					\
+#define SPLAY_LEFT_STEP(root, y, rlist, test) do {		\
+	y = root->left;						\
+	if (y != NULL && (test)) {				\
+		/* Rotate right and make y root. */		\
+		root->left = y->right;				\
+		y->right = root;				\
+		if (root->max_free == y->max_free)		\
+			vm_map_entry_set_max_free(root);	\
+		root = y;					\
+		y = root->left;					\
+	}							\
+	/* Put root on rlist. */				\
+	if (root->max_free == (y != NULL) ?			\
+	    y->max_free : y->next->start - y->end)		\
+		root->max_free = 0;				\
+	root->left = rlist;					\
+	rlist = root;						\
+	root = y;						\
 } while (0)
 
-#define SPLAY_RIGHT_STEP(root, y, llist, test) do {	\
-	y = root->right;				\
-	if (y != NULL && (test)) {			\
-		/* Rotate left and make y root. */	\
-		root->right = y->left;			\
-		y->left = root;				\
-		vm_map_entry_set_max_free(root);	\
-		root = y;				\
-		y = root->right;			\
-	}						\
-	/* Put root on llist. */			\
-	root->right = llist;				\
-	llist = root;					\
-	root = y;					\
+#define SPLAY_RIGHT_STEP(root, y, llist, test) do {		\
+	y = root->right;					\
+	if (y != NULL && (test)) {				\
+		/* Rotate left and make y root. */		\
+		root->right = y->left;				\
+		y->left = root;					\
+		if (root->max_free == y->max_free)		\
+			vm_map_entry_set_max_free(root);	\
+		root = y;					\
+		y = root->right;				\
+	}							\
+	/* Put root on llist. */				\
+	if (root->max_free == (y != NULL) ?			\
+	    y->max_free : y->start - y->prev->end)		\
+		root->max_free = 0;				\
+	root->right = llist;					\
+	llist = root;						\
+	root = y;						\
 } while (0)
 
 /*
@@ -1019,14 +1027,24 @@
 	while (llist != NULL) {
 		y = llist->right;
 		llist->right = ltree;
-		vm_map_entry_set_max_free(llist);
+		if (llist->max_free == 0)
+			vm_map_entry_set_max_free(llist);
+		else
+			llist->max_free = MAX(llist->max_free,
+			    ((ltree != NULL) ? ltree->max_free :
+			     llist->next->start - llist->end));
 		ltree = llist;
 		llist = y;
 	}
 	while (rlist != NULL) {
 		y = rlist->left;
 		rlist->left = rtree;
-		vm_map_entry_set_max_free(rlist);
+		if (rlist->max_free == 0)
+			vm_map_entry_set_max_free(rlist);
+		else
+			rlist->max_free = MAX(rlist->max_free,
+			    ((rtree != NULL) ? rtree->max_free :
+			     rlist->start - rlist->prev->end));
 		rtree = rlist;
 		rlist = y;
 	}