Commit commits all changes that have been made to the root metadata bucket and all of its sub-buckets to the database cache which is periodically synced to persistent storage. In addition, it commits all new blocks directly to persistent storage bypassing the db cache. Blocks can be rather large, so this help increase the amount of cache available for the metadata updates and is safe since blocks are immutable.
This function is part of the database.Tx interface implementation.
} return tx.Commit() }