Projects / lessfs


Lessfs is a high performance inline data deduplicating file system for Linux. Lessfs complies to the POSIX standard and is very useful for backup purposes as well as providing storage for virtual machine images. Although lessfs is a file system that is implemented in user space with FUSE, it offers decent performance. Lessfs is capable of handling data rates up to 350MB/sec. It supports filesystem encryption.

Operating Systems

Recent releases

  •  22 Aug 2010 09:37

    Release Notes: This version adds two new features: synchronous replication and background deletion. Synchronous replication allows Lessfs to support a master/slave configuration. In this case, the master will synchronously replicate the data to the slave. The slave is read-only. The master will freeze forever when the slave becomes unreachable. When background deletion is enabled, lessfs will spawn a background thread that will take care of the truncation/deletion task. Lessfs will therefore return immediately after a delete or truncate operation.

    •  07 Jul 2010 16:04

      Release Notes: The 1.1.0 series of Lessfs adds support for many different hashes including SHA-256, tiger, and whirlpool (64 bytes). Compression has been improved and many compression algorithms are now available, including bzip, gzip, lzo, and deflate. The file_io backend supports encryption. Performance has increased to a level where lessfs outperforms many of its rivals when it comes to write throughput.

      •  31 Mar 2010 14:33

        Release Notes: This release enables lessfs to be mounted without the need to specify options other than the configuration file and the mountpoint. Lessfs now provides automatic migration support for older lessfs versions.

        •  07 Mar 2010 10:05

          Release Notes: This release fixes some minor bugs that are related to logging only.

          •  04 Mar 2010 21:37

            Release Notes: This release enables support for transactions/check pointing. Lessfs no longer needs fsck after a crash. Also new is the ability to run a program when disk space drops below a certain amount of space. This program can be used to free up space when the tokyocabinet datastore is used.

            Recent comments

            15 Jan 2012 20:40 RealDusty

            Version 1.6.0 has been released.

            This version of Lessfs comes with a significant number of changes.
            The multifile_io backend is now fully functional with replication.

            By default Lessfs will now compile with berkeleydb instead of tokyocabinet. Lessfs requires berkeleydb >= 4.8.

            Batch replication has been extensively tested and improved. Some nasty problems that could occur when either the master of the slave suffered an unclean shutdown have been solved.

            In the SPEC files snappy compression is now enabled by default.

            Lessfs-1.6.0 will be the last of the 1.x serie releases that introduces new features. From now on the Lessfs-1.x series will remain frozen and new releases will only contain bug fixes.


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