Differences between JFS and Enhanced JFS
There are many differences between JFS and Enhanced JFS.
| Function | JFS | Enhanced JFS |
|---|---|---|
| Optimization | 32-bit kernel | 64-bit kernel |
| Maximum file system size | 32 TB | 32 TB |
| Maximum file size | 64 GB | 16 TB |
| Number of I-nodes | Fixed at file system creation | Dynamic, limited by disk space |
| Large file support | As mount option | Default |
| Online defragmentation | Yes | Yes |
| namefs | Yes | Yes |
| DMAPI | No | Yes |
| Compression | Yes | No |
| Quotas | Yes | Yes |
| Deferred update | Yes | No |
| Direct I/O support | Yes | Yes |
Note:
- Cloning with a system backup with mksysb from a 64-bit enabled JFS2 system to a 32-bit system will not be successful.
- Unlike the JFS file system, the JFS2 file system will not allow the link() API to be used on its binary type directory. This limitation may cause some applications that operate correctly on a JFS file system to fail on a JFS2 file system.