| Developer(s) | Oracle Corporation |
|---|---|
| Full name | Oracle Cluster file System |
| Introduced | March 2006 withLinux 2.6.16 |
| Limits | |
| Max volume size | 4 PB (OCFS2)[1] |
| Max file size | 4 PB (OCFS2)[1] |
| Max filename length | 255 bytes |
| Allowed filename characters | All bytes exceptNUL and '/' |
| Features | |
| Dates recorded | modification (mtime), attribute modification (ctime), access (atime) |
| File system permissions | Unix permissions,ACLs and arbitrary security attributes (Linux 2.6 and later) |
| Transparent compression | No |
| Transparent encryption | No |
| Data deduplication | No |
| Copy-on-write | Yes |
| Other | |
| Supported operating systems | Linux |
The Oracle Cluster File System (OCFS, in its second versionOCFS2) is ashared disk file system developed byOracle Corporation and released under theGNU General Public License.The first version of OCFS was developed with the main focus to accommodate Oracle'sdatabase management system that usedcluster computing. Because of that it was not aPOSIX-compliant file system. With version 2 the POSIX features were included.
OCFS2 (version 2) was integrated into the version 2.6.16 ofLinux kernel. Initially, it was marked as "experimental" (Alpha-test) code. This restriction was removed in Linux version 2.6.19. With kernel version 2.6.29 in late 2008, more features were included into ocfs2, such asaccess control lists and quotas.[2][3]
OCFS2 used adistributed lock manager which resembles theOpenVMS DLM but is much simpler.[4]Oracle announced version 1.6 in November 2010 which included acopy on write feature called reflink.[5]
