diff --git a/CHANGES b/CHANGES
index 134149d3..b36aa5d8 100644
--- a/CHANGES
+++ b/CHANGES
@@ -19,6 +19,7 @@ LMDB 0.9.17 Release Engineering
 	Fix ITS#8311 page_split from update_key
 	Fix ITS#8312 loose pages in nested txn
 	Fix ITS#8313 mdb_rebalance dummy cursor
+	Fix ITS#8315 dirty_room in nested txn
 	Added mdb_txn_id() (ITS#7994)
 	Added robust mutex support
 	Miscellaneous cleanup/simplification
diff --git a/mdb.c b/mdb.c
index 0c5e6f35..741c7cb3 100644
--- a/mdb.c
+++ b/mdb.c
@@ -5541,6 +5541,7 @@ mdb_ovpage_free(MDB_cursor *mc, MDB_page *mp)
 				return MDB_CORRUPTED;
 			}
 		}
+		txn->mt_dirty_room++;
 		if (!(env->me_flags & MDB_WRITEMAP))
 			mdb_dpage_free(env, mp);
 release:
@@ -6697,6 +6698,7 @@ current:
 						return ENOMEM;
 					id2.mid = pg;
 					id2.mptr = np;
+					/* Note - this page is already counted in parent's dirty_room */
 					rc2 = mdb_mid2l_insert(mc->mc_txn->mt_u.dirty_list, &id2);
 					mdb_cassert(mc, rc2 == 0);
 					if (!(flags & MDB_RESERVE)) {