CentralNotice HAMMER From Wikipedia, the free encyclopedia Jump to: navigation , search For the Marvel Comics organization, see H.A.M.M.E.R . HAMMER Developer Matthew Dillon Full name HAMMER Introduced July 21, 2008 ( DragonFly BSD 2.0 [ 1 ] ) Structures Directory contents B+ tree [ 2 ] Limits Max. volume size 1 EiB [ 2 ] Features Forks no File system permissions UNIX permissions Data deduplication on demand Other Supported operating systems DragonFly BSD HAMMER is a high-availability 64-bit file system developed by Matthew Dillon for DragonFly BSD using B-trees . Its major features include infinite NFS-exportable snapshots , master-multislave operation, configurable history retention, fsckless-mount, and checksums to deal with data corruption . [ 3 ] HAMMER also supports data block deduplication , meaning that identic...