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IceFileSystem (2007-2011)
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| Design goals and priorities |
64bit disk filesystem supporting a high number of useful features, by a design prioritised like following:
| 1-Reliability | 2-Scalability | 3-Efficiency | 4-Speed |
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| Features |
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64bit file/partition/extent sizes (actually very close to 2^63 bytes).
No self imposed fragmentation of large files unless there is not enough
contigious space available.
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All metadata on disk is checksummed.
This means any errors on disk will be detected a lot quicker.
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Meta level jornalling. Journalling makes operations to disk atomic.
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Hardlinks (directory and file), softlinks, notification, examine all,
record locking, file comments. Fully supported.
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Supports sector sizes from 2^9 to 2^31, atleast in theory.
Filesystem layout on disk is not dependant on a specific underlying
sector size. Filesystem may however place data on disk so that it is
optimal for the sector size used.
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Supports blocksizes from 512 bytes to 32 KiB. Still works very well with
small blocksizes though.
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Filesystem does not get slower for larger partitions (scales very well),
or when heavily fragmented.
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No limit in # of files/dirs in partition/dirs.
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Handles removable media.
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Supports optional recycle dir.
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Supports automatically truncated log files and file change log.
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Wastes only 128k (and preallocates another 128k for meta space)
for filesystem administration data, regardless of partition size.
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Dynamic handling of cache memory.
Memory is given back (progressivly) to system when not used.
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| Technical |
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Extent based space and file data layout.
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Main space allocator is based on the TLSF algorithm,
adapted for on-disk storage.
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All metadata except extent headers are located in special extents
called pools and use a local bitmap to keep track of free meta space.
Metadata is very compact.
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Implementation uses two level caching (sector + metadata).
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Implementation supports preallocation to minimize fragmentation (and increase speed)
when several files are concurrently written to.
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| Platforms supported |
- MorphOS (2.x for best performance)
IceFileSystem and all its support tools can be downloaded right here,
latest version is 2.8. (released 2011.11.18)
- AmigaOS 3.x
Coming 2011..maybe :)
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| Tools included |
- FSFormat - Generic formatting application (MUI)
- IceConfig - IceFS configuration application (MUI)
- IceInfo - Displays locks and notifys on IceFS volumes (MUI)
- IceCheck - Check integrity of on-disk layout (CLI)
- LogFileCtrl - Create and change size of logfiles (CLI)
- IceSalv - Simple file salvage tool (CLI)
- ShowLinks - Lists hard and soft links (CLI)
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| Links |
IceDoctor
Mailing-list
Ice2Layout.PDF (WIP)
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| Contact and (c) |
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dev blubbedev net
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