US Patent 9020987 Managing updating of metadata of file systems

A method is used in managing updating of metadata of file systems. Changes in metadata of a file of a file system are stored in a journal upon receiving an I/O request for the file of the file system. The I/O request results in update of metadata of the file of the file system. The journal includes metadata transactions upon the file system. Changes to metadata of the file are stored in a volatile memory of a data storage system upon receiving subsequent I/O requests resulting in update of metadata of the file of the file system. Metadata of the file of the file system is updated with information derived from metadata changes stored in the journal.