Also support NOMETASYNC on txn_begin

diff --git a/libraries/liblmdb/lmdb.h b/libraries/liblmdb/lmdb.h
index 61318ff..d5c70da 100644 (file)
--- a/libraries/liblmdb/lmdb.h
+++ b/libraries/liblmdb/lmdb.h
@@ -932,6 +932,8 @@ int  mdb_env_set_assert(MDB_env *env, MDB_assert_func *func);
         *              This transaction will not perform any write operations.
         *      <li>#MDB_NOSYNC
         *              Don't flush system buffers to disk when committing this transaction.
+        *      <li>#MDB_NOMETASYNC
+        *              Flush system buffers but omit metadata flush when committing this transaction.
         * </ul>
         * @param[out] txn Address where the new #MDB_txn handle will be stored
         * @return A non-zero error value on failure and 0 on success. Some possible

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 984a5bd..ffe0ad4 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -1085,6 +1085,7 @@ struct MDB_txn {
 #define MDB_TXN_DIRTY          0x04            /**< must write, even if dirty list is empty */
 #define MDB_TXN_SPILLS         0x08            /**< txn or a parent has spilled pages */
 #define MDB_TXN_NOSYNC         0x10            /**< don't sync this txn on commit */
+#define MDB_TXN_NOMETASYNC     0x20            /**< don't sync meta for this txn on commit */
 /** @} */
        unsigned int    mt_flags;               /**< @ref mdb_txn */
        /** #dirty_list room: Array size - \#dirty pages visible to this txn.
@@ -2758,6 +2759,8 @@ mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret)
        } else {
                if (flags & MDB_NOSYNC)
                        txn->mt_flags |= MDB_TXN_NOSYNC;
+               if (flags & MDB_NOMETASYNC)
+                       txn->mt_flags |= MDB_TXN_NOMETASYNC;
                txn->mt_cursors = (MDB_cursor **)(txn->mt_dbs + env->me_maxdbs);
                if (parent) {
                        txn->mt_dbiseqs = parent->mt_dbiseqs;
@@ -3688,7 +3691,7 @@ mdb_env_write_meta(MDB_txn *txn)
                __sync_synchronize();
 #endif
                mp->mm_txnid = txn->mt_txnid;
-               if (F_ISSET(txn->mt_flags, MDB_TXN_NOSYNC))
+               if (txn->mt_flags & (MDB_TXN_NOSYNC|MDB_TXN_NOMETASYNC))
                        goto done;
                if (!(env->me_flags & (MDB_NOMETASYNC|MDB_NOSYNC))) {
                        unsigned meta_size = env->me_psize;
@@ -3727,7 +3730,7 @@ mdb_env_write_meta(MDB_txn *txn)
 
        /* Write to the SYNC fd */
        mfd = ((env->me_flags & (MDB_NOSYNC|MDB_NOMETASYNC)) ||
-               (txn->mt_flags & MDB_TXN_NOSYNC)) ?
+               (txn->mt_flags & (MDB_TXN_NOSYNC|MDB_TXN_NOMETASYNC))) ?
                env->me_fd : env->me_mfd;
 #ifdef _WIN32
        {