diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c
index a685241..27f2387 100644
--- a/libraries/libmdb/mdb.c
+++ b/libraries/libmdb/mdb.c
@@ -578,7 +578,7 @@ mdb_dkey(MDB_val *key, char *buf)
 	unsigned int i;
 	if (key->mv_size > MAXKEYSIZE)
 		return "MAXKEYSIZE";
-#if 0
+#if 1
 	for (i=0; i<key->mv_size; i++)
 		ptr += sprintf(ptr, "%02x", *c++);
 #else
@@ -744,7 +744,7 @@ mdb_touch(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *pp)
 			return ENOMEM;
 		DPRINTF("touched db %u page %lu -> %lu", dbi, mp->mp_pgno, dp->p.mp_pgno);
 		assert(mp->mp_pgno != dp->p.mp_pgno);
-		mdb_midl_insert(txn->mt_free_pgs, mp->mp_pgno);
+		mdb_midl_append(txn->mt_free_pgs, mp->mp_pgno);
 		pgno = dp->p.mp_pgno;
 		memcpy(&dp->p, mp, txn->mt_env->me_psize);
 		mp = &dp->p;
@@ -1017,6 +1017,7 @@ mdb_txn_commit(MDB_txn *txn)
 		mc.mc_snum = 0;
 		mdb_search_page(txn, FREE_DBI, &key, &mc, 1, &mpp);
 
+		mdb_midl_sort(txn->mt_free_pgs);
 #if DEBUG > 1
 		{
 			unsigned int i;
@@ -3159,7 +3160,7 @@ mdb_cursor_del(MDB_cursor *mc, unsigned int flags)
 #endif
 						{
 							/* free it */
-							mdb_midl_insert(mc->mc_txn->mt_free_pgs, pg);
+							mdb_midl_append(mc->mc_txn->mt_free_pgs, pg);
 						}
 					}
 					rc = mdb_sibling(&mc->mc_xcursor->mx_cursor, 1);
@@ -3178,7 +3179,7 @@ mdb_cursor_del(MDB_cursor *mc, unsigned int flags)
 #endif
 			{
 				/* free it */
-				mdb_midl_insert(mc->mc_txn->mt_free_pgs,
+				mdb_midl_append(mc->mc_txn->mt_free_pgs,
 					mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_root);
 			}
 		}
@@ -3814,10 +3815,10 @@ mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mpp)
 			txn->mt_dbs[dbi].md_root = P_INVALID;
 			txn->mt_dbs[dbi].md_depth = 0;
 			txn->mt_dbs[dbi].md_leaf_pages = 0;
-			mdb_midl_insert(txn->mt_free_pgs, mpp->mp_page->mp_pgno);
+			mdb_midl_append(txn->mt_free_pgs, mpp->mp_page->mp_pgno);
 		} else if (IS_BRANCH(mpp->mp_page) && NUMKEYS(mpp->mp_page) == 1) {
 			DPUTS("collapsing root page!");
-			mdb_midl_insert(txn->mt_free_pgs, mpp->mp_page->mp_pgno);
+			mdb_midl_append(txn->mt_free_pgs, mpp->mp_page->mp_pgno);
 			txn->mt_dbs[dbi].md_root = NODEPGNO(NODEPTR(mpp->mp_page, 0));
 			if ((rc = mdb_get_page(txn, txn->mt_dbs[dbi].md_root, &root)))
 				return rc;
@@ -3895,7 +3896,7 @@ mdb_del0(MDB_cursor *mc, unsigned int ki, MDB_pageparent *mpp, MDB_node *leaf)
 		ovpages = OVPAGES(NODEDSZ(leaf), mc->mc_txn->mt_env->me_psize);
 		for (i=0; i<ovpages; i++) {
 			DPRINTF("freed ov page %lu", pg);
-			mdb_midl_insert(mc->mc_txn->mt_free_pgs, pg);
+			mdb_midl_append(mc->mc_txn->mt_free_pgs, pg);
 			pg++;
 		}
 	}
diff --git a/libraries/libmdb/midl.c b/libraries/libmdb/midl.c
index 0af517d..17b6e51 100644
--- a/libraries/libmdb/midl.c
+++ b/libraries/libmdb/midl.c
@@ -28,6 +28,7 @@
  */
 #define CMP(x,y)	 ( (x) < (y) ? -1 : (x) > (y) )
 
+#if 0
 static unsigned mdb_midl_search( IDL ids, ID id )
 {
 	/*
@@ -89,6 +90,7 @@ int mdb_midl_insert( IDL ids, ID id )
 
 	if ( x <= ids[0] && ids[x] == id ) {
 		/* duplicate */
+		assert(0);
 		return -1;
 	}
 
@@ -112,6 +114,82 @@ int mdb_midl_insert( IDL ids, ID id )
 
 	return 0;
 }
+#endif
+
+int mdb_midl_append( IDL ids, ID id )
+{
+	/* Too big? */
+	if (ids[0] >= MDB_IDL_UM_SIZE)
+		return -1;
+	ids[0]++;
+	ids[ids[0]] = id;
+	return 0;
+}
+
+/* Quicksort + Insertion sort for small arrays */
+
+#define SMALL	8
+#define	SWAP(a,b)	itmp=(a);(a)=(b);(b)=itmp
+
+void
+mdb_midl_sort( ID *ids )
+{
+	int istack[16*sizeof(int)];
+	int i,j,k,l,ir,jstack;
+	ID a, itmp;
+
+	ir = ids[0];
+	l = 1;
+	jstack = 0;
+	for(;;) {
+		if (ir - l < SMALL) {	/* Insertion sort */
+			for (j=l+1;j<=ir;j++) {
+				a = ids[j];
+				for (i=j-1;i>=1;i--) {
+					if (ids[i] >= a) break;
+					ids[i+1] = ids[i];
+				}
+				ids[i+1] = a;
+			}
+			if (jstack == 0) break;
+			ir = istack[jstack--];
+			l = istack[jstack--];
+		} else {
+			k = (l + ir) >> 1;	/* Choose median of left, center, right */
+			SWAP(ids[k], ids[l+1]);
+			if (ids[l] < ids[ir]) {
+				SWAP(ids[l], ids[ir]);
+			}
+			if (ids[l+1] < ids[ir]) {
+				SWAP(ids[l+1], ids[ir]);
+			}
+			if (ids[l] < ids[l+1]) {
+				SWAP(ids[l], ids[l+1]);
+			}
+			i = l+1;
+			j = ir;
+			a = ids[l+1];
+			for(;;) {
+				do i++; while(ids[i] > a);
+				do j--; while(ids[j] < a);
+				if (j < i) break;
+				SWAP(ids[i],ids[j]);
+			}
+			ids[l+1] = ids[j];
+			ids[j] = a;
+			jstack += 2;
+			if (ir-i+1 >= j-1) {
+				istack[jstack] = ir;
+				istack[jstack-1] = i;
+				ir = j-1;
+			} else {
+				istack[jstack] = j-1;
+				istack[jstack-1] = l;
+				l = i;
+			}
+		}
+	}
+}
 
 unsigned mdb_mid2l_search( ID2L ids, ID id )
 {
diff --git a/libraries/libmdb/midl.h b/libraries/libmdb/midl.h
index 1e6c3c3..8e4a6e3 100644
--- a/libraries/libmdb/midl.h
+++ b/libraries/libmdb/midl.h
@@ -108,6 +108,18 @@ typedef ID *IDL;
 	 */
 int mdb_midl_insert( IDL ids, ID id );
 
+	/** Append an ID onto an IDL.
+	 * @param[in,out] ids	The IDL to append to.
+	 * @param[in] id	The ID to append.
+	 * @return	0 on success, -2 if the IDL is too large.
+	 */
+int mdb_midl_append( IDL ids, ID id );
+
+	/** Sort an IDL.
+	 * @param[in,out] ids	The IDL to sort.
+	 */
+void mdb_midl_sort( IDL ids );
+
 	/** An ID2 is an ID/pointer pair.
 	 */
 typedef struct ID2 {