Hi, I have several questions about the environment options in mdb_env_open.

* MDB_NOSYNC states that as long as the filesystem preserves the write order, the database will lose durability, but preserve ACI. If we're using EXT4, does that mean we must mount the filesystem with "data=ordered" so LMDB will preserve ACI when used in combination with MDB_NOSYNC? Are there any other mount options we should use so we don't lose ACI? * MDB_MAPASYNC states it has the same corruption potential as MDB_NOSYNC. Does it preserve ACI if the filesystem preserves the write order like MDB_NOSYNC? * The docs states that (MDB_MAPASYNC | MDB_WRITEMAP) may be preferable over MDB_NOSYNC. When would you want to use one over the other? Is there a good rule of thumb to follow if you have to use one of these options?

Thanks