Granular buffering of metadata changes for journaling file systems

摘要

Responsive to determining an in-memory image of a metadata disk block, a buffer is generated in memory and includes metadata updates made to the metadata disk block. Metadata updates to the disk block by a first transaction are recorded and stored in the buffer. Transfer of metadata updates that are logically complete, but remain in an active transaction list stored in the buffer, are delayed to a completed transaction list, scheduled to be written to a log file on disk at a subsequent time. A determination is made as to whether the metadata disk block is deleted by a second transaction following the first, and responsive to determining the metadata disk block is to be deleted and the metadata updates of the second transaction transfer to the completed transaction list, preventing the writing of the metadata updates to the log file and the metadata disk block to disk.