diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c
index 291bd22..9c6af1e 100644
--- a/libraries/libmdb/mdb.c
+++ b/libraries/libmdb/mdb.c
@@ -252,12 +252,13 @@ typedef struct MDB_ppage {					/* ordered list of pages */
 
 #define CURSOR_TOP(c)		 (&(c)->mc_stack[(c)->mc_snum-1])
 #define CURSOR_PARENT(c)	 (&(c)->mc_stack[(c)->mc_snum-2])
+#define CURSOR_STACK		 32
 
 struct MDB_xcursor;
 
 struct MDB_cursor {
 	MDB_txn		*mc_txn;
-	MDB_ppage	mc_stack[32];		/* stack of parent pages */
+	MDB_ppage	mc_stack[CURSOR_STACK];		/* stack of parent pages */
 	unsigned int	mc_snum;		/* number of pushed pages */
 	MDB_dbi		mc_dbi;
 	short		mc_initialized;	/* 1 if initialized */
@@ -377,7 +378,7 @@ static int  mdb_search_page(MDB_txn *txn,
 static int  mdb_env_read_header(MDB_env *env, MDB_meta *meta);
 static int  mdb_env_read_meta(MDB_env *env, int *which);
 static int  mdb_env_write_meta(MDB_txn *txn);
-static MDB_page *mdb_get_page(MDB_txn *txn, pgno_t pgno);
+static int  mdb_get_page(MDB_txn *txn, pgno_t pgno, MDB_page **mp);
 
 static MDB_node *mdb_search_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp,
 			    MDB_val *key, int *exactp, unsigned int *kip);
@@ -677,6 +678,7 @@ mdb_touch(MDB_txn *txn, MDB_pageparent *pp)
 		if ((dp = mdb_alloc_page(txn, pp->mp_parent, pp->mp_pi, 1)) == NULL)
 			return ENOMEM;
 		DPRINTF("touched page %lu -> %lu", 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);
 		pgno = dp->p.mp_pgno;
 		memcpy(&dp->p, mp, txn->mt_env->me_psize);
@@ -718,18 +720,6 @@ mdb_txn_renew0(MDB_txn *txn)
 		return MDB_PANIC;
 	}
 
-	if (!(txn->mt_flags & MDB_TXN_RDONLY)) {
-		txn->mt_u.dirty_list = env->me_dirty_list;
-		txn->mt_u.dirty_list[0].mid = 0;
-		txn->mt_free_pgs = env->me_free_pgs;
-		txn->mt_free_pgs[0] = 0;
-
-		pthread_mutex_lock(&env->me_txns->mti_wmutex);
-		env->me_txns->mti_txnid++;
-	}
-
-	txn->mt_txnid = env->me_txns->mti_txnid;
-
 	if (txn->mt_flags & MDB_TXN_RDONLY) {
 		MDB_reader *r = pthread_getspecific(env->me_txkey);
 		if (!r) {
@@ -750,9 +740,17 @@ mdb_txn_renew0(MDB_txn *txn)
 				env->me_txns->mti_numreaders = i+1;
 			pthread_mutex_unlock(&env->me_txns->mti_mutex);
 		}
+		txn->mt_txnid = env->me_txns->mti_txnid;
 		r->mr_txnid = txn->mt_txnid;
 		txn->mt_u.reader = r;
 	} else {
+		pthread_mutex_lock(&env->me_txns->mti_wmutex);
+
+		txn->mt_txnid = env->me_txns->mti_txnid+1;
+		txn->mt_u.dirty_list = env->me_dirty_list;
+		txn->mt_u.dirty_list[0].mid = 0;
+		txn->mt_free_pgs = env->me_free_pgs;
+		txn->mt_free_pgs[0] = 0;
 		env->me_txn = txn;
 	}
 
@@ -776,8 +774,9 @@ mdb_txn_renew0(MDB_txn *txn)
 		txn->mt_next_pgno = env->me_meta->mm_last_pg+1;
 	}
 
-	DPRINTF("begin transaction %lu on mdbenv %p, root page %lu",
-		txn->mt_txnid, (void *) env, txn->mt_dbs[MAIN_DBI].md_root);
+	DPRINTF("begin txn %p %lu%c on mdbenv %p, root page %lu", txn,
+		txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w',
+		(void *) env, txn->mt_dbs[MAIN_DBI].md_root);
 
 	return MDB_SUCCESS;
 }
@@ -862,7 +861,6 @@ mdb_txn_reset0(MDB_txn *txn)
 		}
 
 		env->me_txn = NULL;
-		env->me_txns->mti_txnid--;
 		for (i=2; i<env->me_numdbs; i++)
 			env->me_dbxs[i].md_dirty = 0;
 		pthread_mutex_unlock(&env->me_txns->mti_wmutex);
@@ -933,7 +931,7 @@ mdb_txn_commit(MDB_txn *txn)
 	if (!txn->mt_u.dirty_list[0].mid)
 		goto done;
 
-	DPRINTF("committing transaction %lu on mdbenv %p, root page %lu",
+	DPRINTF("committing txn %p %lu on mdbenv %p, root page %lu", txn,
 	    txn->mt_txnid, (void *) env, txn->mt_dbs[MAIN_DBI].md_root);
 
 	/* should only be one record now */
@@ -1034,6 +1032,7 @@ mdb_txn_commit(MDB_txn *txn)
 			dp->p.mp_flags &= ~P_DIRTY;
 			if (++n >= MDB_COMMIT_PAGES) {
 				done = 0;
+				i++;
 				break;
 			}
 		}
@@ -1067,6 +1066,7 @@ mdb_txn_commit(MDB_txn *txn)
 		}
 		txn->mt_u.dirty_list[i].mid = 0;
 	}
+	txn->mt_u.dirty_list[0].mid = 0;
 
 	if ((n = mdb_env_sync(env, 0)) != 0 ||
 	    (n = mdb_env_write_meta(txn)) != MDB_SUCCESS) {
@@ -1074,6 +1074,8 @@ mdb_txn_commit(MDB_txn *txn)
 		return n;
 	}
 
+	env->me_txns->mti_txnid = txn->mt_txnid;
+
 done:
 	env->me_txn = NULL;
 	/* update the DB tables */
@@ -1694,17 +1696,18 @@ cursor_push_page(MDB_cursor *cursor, MDB_page *mp)
 	DPRINTF("pushing page %lu on db %u cursor %p", mp->mp_pgno,
 		cursor->mc_dbi, (void *) cursor);
 
+	assert(cursor->mc_snum < CURSOR_STACK);
+
 	ppage = &cursor->mc_stack[cursor->mc_snum++];
 	ppage->mp_page = mp;
 	ppage->mp_ki = 0;
 	return ppage;
 }
 
-static MDB_page *
-mdb_get_page(MDB_txn *txn, pgno_t pgno)
+static int
+mdb_get_page(MDB_txn *txn, pgno_t pgno, MDB_page **ret)
 {
 	MDB_page *p = NULL;
-	int found = 0;
 
 	if (!F_ISSET(txn->mt_flags, MDB_TXN_RDONLY) && txn->mt_u.dirty_list[0].mid) {
 		MDB_dpage *dp;
@@ -1715,15 +1718,18 @@ mdb_get_page(MDB_txn *txn, pgno_t pgno)
 		if (x <= txn->mt_u.dirty_list[0].mid && txn->mt_u.dirty_list[x].mid == pgno) {
 			dp = txn->mt_u.dirty_list[x].mptr;
 			p = &dp->p;
-			found = 1;
 		}
 	}
-	if (!found) {
-		if (pgno > txn->mt_env->me_meta->mm_last_pg)
-			return NULL;
-		p = (MDB_page *)(txn->mt_env->me_map + txn->mt_env->me_psize * pgno);
+	if (!p) {
+		if (pgno <= txn->mt_env->me_meta->mm_last_pg)
+			p = (MDB_page *)(txn->mt_env->me_map + txn->mt_env->me_psize * pgno);
+	}
+	*ret = p;
+	if (!p) {
+		DPRINTF("page %lu not found", pgno);
+		assert(p != NULL);
 	}
-	return p;
+	return (p != NULL) ? MDB_SUCCESS : MDB_PAGE_NOTFOUND;
 }
 
 static int
@@ -1771,8 +1777,8 @@ mdb_search_page_root(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
 			CURSOR_TOP(cursor)->mp_ki = i;
 
 		mpp->mp_parent = mp;
-		if ((mp = mdb_get_page(txn, NODEPGNO(node))) == NULL)
-			return MDB_PAGE_NOTFOUND;
+		if ((rc = mdb_get_page(txn, NODEPGNO(node), &mp)))
+			return rc;
 		mpp->mp_pi = i;
 		mpp->mp_page = mp;
 
@@ -1831,10 +1837,11 @@ mdb_search_page(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
 		return MDB_NOTFOUND;
 	}
 
-	if ((mpp->mp_page = mdb_get_page(txn, root)) == NULL)
-		return MDB_PAGE_NOTFOUND;
+	if (rc = mdb_get_page(txn, root, &mpp->mp_page))
+		return rc;
 
-	DPRINTF("root page has flags 0x%X", mpp->mp_page->mp_flags);
+	DPRINTF("db %u root page %lu has flags 0x%X",
+		dbi, root,  mpp->mp_page->mp_flags);
 
 	if (modify) {
 		/* For sub-databases, update main root first */
@@ -1863,6 +1870,7 @@ mdb_read_data(MDB_txn *txn, MDB_node *leaf, MDB_val *data)
 {
 	MDB_page	*omp;		/* overflow mpage */
 	pgno_t		 pgno;
+	int rc;
 
 	if (!F_ISSET(leaf->mn_flags, F_BIGDATA)) {
 		data->mv_size = leaf->mn_dsize;
@@ -1874,9 +1882,9 @@ mdb_read_data(MDB_txn *txn, MDB_node *leaf, MDB_val *data)
 	 */
 	data->mv_size = leaf->mn_dsize;
 	memcpy(&pgno, NODEDATA(leaf), sizeof(pgno));
-	if ((omp = mdb_get_page(txn, pgno)) == NULL) {
+	if (rc = mdb_get_page(txn, pgno, &omp)) {
 		DPRINTF("read overflow page %lu failed", pgno);
-		return MDB_PAGE_NOTFOUND;
+		return rc;
 	}
 	data->mv_data = METADATA(omp);
 
@@ -1970,8 +1978,8 @@ mdb_sibling(MDB_cursor *cursor, int move_right)
 	assert(IS_BRANCH(parent->mp_page));
 
 	indx = NODEPTR(parent->mp_page, parent->mp_ki);
-	if ((mp = mdb_get_page(cursor->mc_txn, NODEPGNO(indx))) == NULL)
-		return MDB_PAGE_NOTFOUND;
+	if (rc = mdb_get_page(cursor->mc_txn, NODEPGNO(indx), &mp))
+		return rc;;
 #if 0
 	mp->parent = parent->mp_page;
 	mp->parent_index = parent->mp_ki;
@@ -2681,6 +2689,7 @@ mdb_xcursor_init1(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx, MDB_node *node)
 	} else {
 		dbn = 2;
 	}
+	DPRINTF("Sub-db %u for db %u root page %lu", dbn, dbi, db->md_root);
 	mx->mx_dbs[dbn] = *db;
 	mx->mx_dbxs[dbn].md_name.mv_data = NODEKEY(node);
 	mx->mx_dbxs[dbn].md_name.mv_size = node->mn_ksize;
@@ -2987,6 +2996,7 @@ mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mpp)
 	MDB_page	*root;
 	MDB_pageparent npp;
 	indx_t		 si = 0, di = 0;
+	int rc;
 
 	assert(txn != NULL);
 	assert(mpp != NULL);
@@ -3010,8 +3020,8 @@ mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mpp)
 		} else if (IS_BRANCH(mpp->mp_page) && NUMKEYS(mpp->mp_page) == 1) {
 			DPUTS("collapsing root page!");
 			txn->mt_dbs[dbi].md_root = NODEPGNO(NODEPTR(mpp->mp_page, 0));
-			if ((root = mdb_get_page(txn, txn->mt_dbs[dbi].md_root)) == NULL)
-				return MDB_PAGE_NOTFOUND;
+			if (rc = mdb_get_page(txn, txn->mt_dbs[dbi].md_root, &root))
+				return rc;
 			txn->mt_dbs[dbi].md_depth--;
 			txn->mt_dbs[dbi].md_branch_pages--;
 		} else
@@ -3036,8 +3046,8 @@ mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mpp)
 		 */
 		DPUTS("reading right neighbor");
 		node = NODEPTR(mpp->mp_parent, mpp->mp_pi + 1);
-		if ((npp.mp_page = mdb_get_page(txn, NODEPGNO(node))) == NULL)
-			return MDB_PAGE_NOTFOUND;
+		if (rc = mdb_get_page(txn, NODEPGNO(node), &npp.mp_page))
+			return rc;
 		npp.mp_pi = mpp->mp_pi + 1;
 		si = 0;
 		di = NUMKEYS(mpp->mp_page);
@@ -3046,8 +3056,8 @@ mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mpp)
 		 */
 		DPUTS("reading left neighbor");
 		node = NODEPTR(mpp->mp_parent, mpp->mp_pi - 1);
-		if ((npp.mp_page = mdb_get_page(txn, NODEPGNO(node))) == NULL)
-			return MDB_PAGE_NOTFOUND;
+		if (rc = mdb_get_page(txn, NODEPGNO(node), &npp.mp_page))
+			return rc;
 		npp.mp_pi = mpp->mp_pi - 1;
 		si = NUMKEYS(npp.mp_page) - 1;
 		di = 0;
@@ -3178,7 +3188,7 @@ mdb_del(MDB_txn *txn, MDB_dbi dbi,
 							top = parent;
 						} else {
 							ni = NODEPTR(parent->mp_page, parent->mp_ki);
-							top->mp_page = mdb_get_page(&mx.mx_txn, NODEPGNO(ni));
+							rc = mdb_get_page(&mx.mx_txn, NODEPGNO(ni), &top->mp_page);
 						}
 					}
 				}