Function lmdb_master_sys::mdb_txn_reset

pub unsafe extern "C" fn mdb_txn_reset(txn: *mut MDB_txn)

Reset a read-only transaction.

Abort the transaction like #mdb_txn_abort(), but keep the transaction handle. #mdb_txn_renew() may reuse the handle. This saves allocation overhead if the process will start a new read-only transaction soon, and also locking overhead if #MDB_NOTLS is in use. The reader table lock is released, but the table slot stays tied to its thread or #MDB_txn. Use mdb_txn_abort() to discard a reset handle, and to free its lock table slot if MDB_NOTLS is in use. Cursors opened within the transaction must not be used again after this call, except with #mdb_cursor_renew(). Reader locks generally don’t interfere with writers, but they keep old versions of database pages allocated. Thus they prevent the old pages from being reused when writers commit new data, and so under heavy load the database size may grow much more rapidly than otherwise.

Arguments

• txn (direction in) - A transaction handle returned by #mdb_txn_begin()