1579 lines
58 KiB
ReStructuredText
1579 lines
58 KiB
ReStructuredText
Changes (kernel/version)
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========================
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Summary of kernel changes for each version.
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6.x
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---
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6.0 (Oct 2022)
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^^^^^^^^^^^^^^
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- sysfs updates:
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- export chunk size, in debug mode add tunable for setting its size
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- show zoned among features (was only in debug mode)
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- show commit stats (number, last/max/total duration)
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- mixed_backref and big_metadata sysfs feature files removed, they've
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been default for sufficiently long time, there are no known users and
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mixed_backref could be confused with mixed_groups
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- send protocol updated to version 2
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- new commands:
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- ability write larger data chunks than 64K
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- send raw compressed extents (uses the encoded data ioctls), ie. no
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decompression on send side, no compression needed on receive side
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if supported
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- send 'otime' (inode creation time) among other timestamps
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- send file attributes (a.k.a file flags and xflags)
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- this is first version bump, backward compatibility on send and
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receive side is provided
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- there are still some known and wanted commands that will be
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implemented in the near future, another version bump will be needed,
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however we want to minimize that to avoid causing usability issues
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- print checksum type and implementation at mount time
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- don't print some messages at mount (mentioned as people asked about
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it), we want to print messages namely for new features so let's make
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some space for that:
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- big metadata - this has been supported for a long time and is not a feature
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that's worth mentioning
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- skinny metadata - same reason, set by default by mkfs
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Performance improvements:
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- reduced amount of reserved metadata for delayed items
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- when inserted items can be batched into one leaf
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- when deleting batched directory index items
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- when deleting delayed items used for deletion
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- overall improved count of files/sec, decreased subvolume lock
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contention
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- metadata item access bounds checker micro-optimized, with a few
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percent of improved runtime for metadata-heavy operations
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- increase direct io limit for read to 256 sectors, improved throughput
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by 3x on sample workload
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Notable fixes:
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- raid56
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- reduce parity writes, skip sectors of stripe when there are no data updates
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- restore reading from stripe cache instead of triggering new read
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- refuse to replay log with unknown incompat read-only feature bit set
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- tree-checker verifies if extent items don't overlap
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- check that subvolume is writable when changing xattrs from security
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namespace
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- fix space cache corruption and potential double allocations; this is
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a rare bug but can be serious once it happens, stable backports and
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analysis tool will be provided
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- zoned:
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- fix page locking when COW fails in the middle of allocation
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- improved tracking of active zones, ZNS drives may limit the number
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and there are ENOSPC errors due to that limit and not actual lack of
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space
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- adjust maximum extent size for zone append so it does not cause late
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ENOSPC due to underreservation
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- mirror reading error messages show the mirror number
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- don't fallback to buffered IO for NOWAIT direct IO writes, we don't
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have the NOWAIT semantics for buffered io yet
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- send, fix sending link commands for existing file paths when there are
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deleted and created hardlinks for same files
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- repair all mirrors for profiles with more than 1 copy (raid1c34)
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- fix repair of compressed extents, unify where error detection and
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repair happen
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6.1 (Dec 2022)
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^^^^^^^^^^^^^^
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Performance:
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- outstanding FIEMAP speed improvements:
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- algorithmic change how extents are enumerated leads to orders of
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magnitude speed boost (uncached and cached)
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- extent sharing check speedup (2.2x uncached, 3x cached)
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- add more cancellation points, allowing to interrupt seeking in files
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with large number of extents
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- more efficient hole and data seeking (4x uncached, 1.3x cached)
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- sample results:
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256M, 32K extents: 4s -> 29ms (~150x)
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512M, 64K extents: 30s -> 59ms (~550x)
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1G, 128K extents: 225s -> 120ms (~1800x)
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- improved inode logging, especially for directories (on dbench workload
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throughput +25%, max latency -21%)
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- improved buffered IO, remove redundant extent state tracking, lowering
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memory consumption and avoiding rb tree traversal
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- add sysfs tunable to let qgroup temporarily skip exact accounting when
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deleting snapshot, leading to a speedup but requiring a rescan after
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that, will be used by snapper
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- support io_uring and buffered writes, until now it was just for direct
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IO, with the no-wait semantics implemented in the buffered write path
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it now works and leads to speed improvement in IOPS (2x), throughput
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(2.2x), latency (depends, 2x to 150x)
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- small performance improvements when dropping and searching for extent
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maps as well as when flushing delalloc in COW mode (throughput +5MB/s)
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User visible changes:
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- new incompatible feature block-group-tree adding a dedicated tree for
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tracking block groups, this allows a much faster load during mount and
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avoids seeking unlike when it's scattered in the extent tree items
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- this reduces mount time for many-terabyte sized filesystems
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- conversion tool will be provided so existing filesystem can also be
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updated in place
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- to reduce test matrix and feature combinations requires no-holes
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and free-space-tree (mkfs defaults since 5.15)
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- improved reporting of super block corruption detected by scrub
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- scrub also tries to repair super block and does not wait until next
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commit
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- discard stats and tunables are exported in sysfs
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(/sys/fs/btrfs/FSID/discard)
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- qgroup status is exported in sysfs (/sys/sys/fs/btrfs/FSID/qgroups/)
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- verify that super block was not modified when thawing filesystem
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Fixes:
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- FIEMAP fixes:
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- fix extent sharing status, does not depend on the cached status where merged
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- flush delalloc so compressed extents are reported correctly
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- fix alignment of VMA for memory mapped files on THP
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- send: fix failures when processing inodes with no links (orphan files
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and directories)
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- handle more corner cases for read-only compat feature verification
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- fix crash on raid0 filesystems created with <5.4 mkfs.btrfs that could
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lead to division by zero
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Core:
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- preliminary support for fs-verity in send
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- more effective memory use in scrub for subpage where sector is smaller
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than page
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- block group caching progress logic has been removed, load is now
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synchronous
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- add no-wait semantics to several functions (tree search, nocow,
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flushing, buffered write
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6.2 (Feb 2023)
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^^^^^^^^^^^^^^
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User visible features:
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- raid56 reliability vs performance trade off:
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- fix destructive RMW for raid5 data (raid6 still needs work) - do full RMW
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cycle for writes and verify all checksums before overwrite, this should
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prevent rewriting potentially corrupted data without notice
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- stripes are cached in memory which should reduce the performance impact but
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still can hurt some workloads
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- checksums are verified after repair again
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- this is the last option without introducing additional features (write
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intent bitmap, journal, another tree), the RMW cycle was supposed to be
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avoided by the original implementation exactly for performance reasons but
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that caused all the reliability problems
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- discard=async by default for devices that support it
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- implement emergency flush reserve to avoid almost all unnecessary transaction
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aborts due to ENOSPC in cases where there are too many delayed refs or
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delayed allocation
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- skip block group synchronization if there's no change in used bytes, can
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reduce transaction commit count for some workloads
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- print more specific errors to system log when device scan ioctl fails
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Performance improvements:
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- fiemap and lseek:
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- overall speedup due to skipping unnecessary or duplicate searches (-40% run time)
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- cache some data structures and sharedness of extents (-30% run time)
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- send:
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- faster backref resolution when finding clones
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- cached leaf to root mapping for faster backref walking
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- improved clone/sharing detection
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- overall run time improvements (-70%)
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Fixes:
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- fix compat ro feature check at read-write remount
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- handle case when read-repair happens with ongoing device replace
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- reset defrag ioctl buffer on memory allocation error
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- fix potential crash in quota when rescan races with disable
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- fix qgroup accounting warning when rescan can be started at time with
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temporarily disabled accounting
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- don't cache a single-device filesystem device to avoid cases when a
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loop device is reformatted and the entry gets stale
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- limit number of send clones by maximum memory allocated
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6.3 (? 2023)
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^^^^^^^^^^^^
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Features:
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- block group allocation class heuristics:
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- pack files by size (up to 128k, up to 8M, more) to avoid
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fragmentation in block groups, assuming that file size and life time
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is correlated, in particular this may help during balance
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- with tracepoints and extensible in the future
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- sysfs export of per-device fsid in DEV_INFO ioctl to distinguish seeding
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devices, needed for testing
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- print sysfs stats for the allocation classes
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Performance:
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- send: cache directory utimes and only emit the command when necessary
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- speedup up to 10x
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- smaller final stream produced (no redundant utimes commands issued),
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- compatibility not affected
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- fiemap:
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- skip backref checks for shared leaves
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- speedup 3x on sample filesystem with all leaves shared (e.g. on
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snapshots)
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- micro optimized b-tree key lookup, speedup in metadata operations
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(sample benchmark: fs_mark +10% of files/sec)
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Core changes:
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- change where checksumming is done in the io path
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- checksum and read repair does verification at lower layer
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- cascaded cleanups and simplifications
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Fixes:
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- sysfs: make sure that a run-time change of a feature is correctly
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tracked by the feature files
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- scrub: better reporting of tree block errors
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- fix calculation of unusable block group space reporting bogus values
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due to 32/64b division
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- fix unnecessary increment of read error stat on write error
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- scan block devices in non-exclusive mode to avoid temporary mkfs
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failures
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- fix fast checksum detection, this affects filesystems with non-crc32c
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checksum, calculation would not be offloaded to worker threads (since 5.4)
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- restore thread_pool mount option behaviour for endio workers, the
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new value for maximum active threads would not be set to the actual
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work queues (since 6.0)
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5.x
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---
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5.0 (Mar 2019)
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^^^^^^^^^^^^^^
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Features, hilights:
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- swapfile support (with some limitations)
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- metadata uuid - new feature that allows fast uuid change without rewriting all metadata blocks (backward incompatible)
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- balance messages in the syslog when operations start or stop
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Fixes:
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- improved check of filesystem id associated with a device during scan to
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detect duplicate devices that could be mixed up during mount
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- fix device replace state transitions
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- fix a crash due to a race when quotas are enabled during snapshot creation
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- GFP_NOFS/memalloc_nofs_* fixes
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- fsync fixes
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Other:
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- remove first phase of balance that tried to remove some space (not necessary)
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- separate reserve for delayed refs from global reserve
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- cleanups
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- see [https://git.kernel.org/linus/32ee34eddad13cd44ad0cb3e659fe6fd49143b62 pull request]
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5.1 (May 2019)
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^^^^^^^^^^^^^^
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New features, hilights:
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- zstd compression levels can be set as mount options
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- new ioctl to unregister scanned devices
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- scrub prints messages about start/stop/cancel to the log
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Other changes:
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- qgroups skip some work (est. speedup during balance 20%)
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- reclaim vs GFP_KERNEL fixes
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- fsync fixes for rename/unlink/rmdir
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- improved enospc handling on a highly fragmented filesystem
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- no trim on filesystem with unreplayed log
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- see [https://git.kernel.org/linus/b1e243957e9b3ba8e820fb8583bdf18e7c737aa2 pull request]
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5.2 (Jul 2019)
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^^^^^^^^^^^^^^
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User visible changes, hilights:
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- better read time and write checks to catch errors early and before writing data to disk
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- qgroups + metadata relocation: last speed up patch in the series there should
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be no overhead comparing balance with and without qgroups
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- FIEMAP ioctl does not start a transaction unnecessarily
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- LOGICAL_INO (v1, v2) does not start transaction unnecessarily
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- fsync on files with many (but not too many) hardlinks is faster
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- send tries harder to find ranges to clone
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- trim/discard will skip unallocated chunks that haven't been touched since the last mount
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- tree-checker does more validations: device item, inode item, block group item:
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- improved space flushing logic for intense DIO vs buffered workloads
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- metadata reservations for delalloc reworked to better adapt in many-writers/low-space scenarios
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Fixes:
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- send flushes delayed allocation before start
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- fix fallocate with qgroups accounting underflow
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- send and dedupe can't be run at the same time
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- fix crash in relocation/balance after resume
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Other:
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- new tracepoints for locking
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- async write preallocates memory to avoid failures deep in call chains
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- lots of cleanups
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- see [https://git.kernel.org/linus/9f2e3a53f7ec9ef55e9d01bc29a6285d291c151e pull request]
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5.3 (Sep 2019)
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^^^^^^^^^^^^^^
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New features, hilights:
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- chunks that have been trimmed and unchanged since last mount are tracked and skipped on repeated trims
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- use hw assisted crc32c on more arches
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- the RAID56 incompat bit is automatically removed when the last block group of that type is removed
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Fixes:
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- update ctime/mtime/iversion after hole punching
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- fsync fixes
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- send and balance can't be run at the same time
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Other:
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- code refactoring, file splits
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- preparatory work for more checksums
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- tree checker to verify lengths of various items
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- delayed iput happens at unlink time, not in cleaner thread
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- new tracepoints for space updates
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- see [https://git.kernel.org/linus/a18f8775419d3df282dd83efdb51c5a64d092f31 pull request]
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5.4 (Nov 2019)
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^^^^^^^^^^^^^^
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- tree checker: adde sanity checks for tree items, extent items, and references
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- deprecated subvolume creation mode BTRFS_SUBVOL_CREATE_ASYNC
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- qgroup relation deletion tries harder, orphan entries are removed too
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- space handling improvements (ticket reservations, flushing, overcommit logic)
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- fix possible lockups during send of large subvolumes
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- see [https://git.kernel.org/linus/7d14df2d280fb7411eba2eb96682da0683ad97f6 pull request]
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5.5 (Jan 2020)
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^^^^^^^^^^^^^^
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- new block group profiles: RAID1 with 3- and 4- copies
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- RAID1 in btrfs has always 2 copies, now add support for 3 and 4
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- this is an incompat feature (named RAID1C34)
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- recommended use of RAID1C3 is replacement of RAID6 profile on metadata,
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this brings a more reliable resiliency against 2 device loss/damage
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- support for new checksums
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- per-filesystem, set at mkfs time
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- fast hash (crc32c successor): xxhash, 64bit digest
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- strong hashes (both 256bit): sha256 (slower, FIPS), blake2b (faster)
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- speed up lseek, don't take inode locks unnecessarily, this can speed up parallel SEEK_CUR/SEEK_SET/SEEK_END by 80%
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- send:
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- allow clone operations within the same file
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- limit maximum number of sent clone references to avoid slow backref walking
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- error message improvements: device scan prints process name and PID
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- new tree-checker sanity tests (INODE_ITEM, DIR_ITEM, DIR_INDEX, INODE_REF, XATTR)
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- more in the [https://git.kernel.org/linus/97d0bf96a0d0986f466c3ff59f2ace801e33dc69 pull request]
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5.6 (Mar 2020)
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^^^^^^^^^^^^^^
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Highlights:
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- async discard
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- "mount -o discard=async" to enable it
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- freed extents are not discarded immediatelly, but grouped together and
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trimmed later, with IO rate limiting
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- the actual discard IO requests have been moved out of transaction commit
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to a worker thread, improving commit latency
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- IO rate and request size can be tuned by sysfs files, for now enabled only
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with CONFIG_BTRFS_DEBUG as we might need to add/delete the files and don't
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have a stable-ish ABI for general use, defaults are conservative
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- export device state info in sysfs, e.g. missing, writeable
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- no discard of extents known to be untouched on disk (e.g. after reservation)
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- device stats reset is logged with process name and PID that called the ioctl
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Core changes:
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- qgroup assign returns ENOTCONN when quotas not enabled, used to return EINVAL
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that was confusing
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- device closing does not need to allocate memory anymore
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- snapshot aware code got removed, disabled for years due to performance
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problems, reimplmentation will allow to select wheter defrag breaks or does
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not break COW on shared extents
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- tree-checker:
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- check leaf chunk item size, cross check against number of stripes
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- verify location keys for DIR_ITEM, DIR_INDEX and XATTR items
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- new self test for physical -> logical mapping code, used for super block range exclusion
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Fixes:
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- fix missing hole after hole punching and fsync when using NO_HOLES
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- writeback: range cyclic mode could miss some dirty pages and lead to OOM
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- two more corner cases for metadata_uuid change after power loss during the change
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- fix infinite loop during fsync after mix of rename operations
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- see [https://git.kernel.org/linus/81a046b18b331ed6192e6fd9ff6d12a1f18058cf pull request]
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5.7 (May 2020)
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^^^^^^^^^^^^^^
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Hilights:
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- v2 of ioctl to delete subvolumes, allowing to delete by id and more future extensions
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- removal of obsolete ioctl flag BTRFS_SUBVOL_CREATE_ASYNC
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- more responsive balance cancel
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- speedup of extent back reference resolution
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- reflink/clone_range works on inline extents
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- lots of othe core changes, see the [https://git.kernel.org/linus/15c981d16d70e8a5be297fa4af07a64ab7e080ed pull request]
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5.8 (Aug 2020)
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^^^^^^^^^^^^^^
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Hilights:
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- speedup dead root detection during orphan cleanup
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- send will emit file capabilities after chown
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Core changes:
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- improved global block reserve utilization
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- direct io cleanups and fixes
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- refactored block group reading code
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- lots of other core changes see the [https://git.kernel.org/linus/f3cdc8ae116e27d84e1f33c7a2995960cebb73ac pull request]
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5.9 (Oct 2020)
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^^^^^^^^^^^^^^
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Hilights:
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- add mount option ''rescue'' to unify options for various recovery tasks on a mounted filesystems
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- mount option ''inode_cache'' is deprecated and will be removed in 5.11
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- removed deprecated options ''alloc_start'' and ''subvolrootid''
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- sysfs exports information about qgroups and relations
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- FS_INFO ioctl exports more information from the filesystem (notably type of checksum)
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- running balance detects Ctrl-C too
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- performance improvements in fsync
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- mount-time prefetch of chunk tree
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- for other changes see the [https://git.kernel.org/linus/6dec9f406c1f2de6d750de0fc9d19872d9c4bf0d pull request]
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5.10 (Dec 2020)
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^^^^^^^^^^^^^^^
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Hilights:
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- performance improvements in fsync (dbench workload: higher throughput, lower latency)
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- sysfs exports current exclusive operataion (balance, resize, device add/del/...)
|
|
- sysfs exports supported send stream version
|
|
|
|
Core:
|
|
|
|
- direct io uses iomap infrastructure (no more ''struct buffer_head'')
|
|
- space reservations for data now use ticket infrastructure
|
|
- cleanups, refactoring, preparatory work
|
|
- error handling improvements
|
|
- fixes
|
|
- for other changes see the [https://git.kernel.org/linus/11e3235b4399f7e626caa791a68a0ea8337f6683 pull request]
|
|
|
|
5.11 (Feb 2021)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- new mount option ''rescue'', various modes how to access a damaged filesystem
|
|
- sysfs updates: filesystem generation, supported ''rescue'' modes, read mirror policy
|
|
- removed feature: ''mount -o inode_cache''
|
|
- free space tree fixes, v1 cache removed during conversion
|
|
|
|
Core:
|
|
|
|
- locking switched to standard rw semaphores
|
|
- direct IO ported to iomap infrastructure
|
|
- zoned allocation mode preparation
|
|
- subpage blocksize preparation
|
|
- various performance improvements (skipping unnecessary work)
|
|
- for other changes see the [https://git.kernel.org/linus/f1ee3b8829006b3fda999f00f0059aa327e3f3d0 pull request]
|
|
|
|
5.12 (Apr 2021)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Features:
|
|
|
|
- zoned mode (SMR/ZBC/ZNS friendly allocation mode), first working version with limitations
|
|
- misc performance improvements
|
|
|
|
- flushing and ticket space reservations
|
|
- preemptive background flushing
|
|
- less lock contention for delayed refs
|
|
- dbench-like workload (+7% throughput, -20% latency)
|
|
|
|
Core changes:
|
|
|
|
- subpage block size support peparations
|
|
|
|
Fixes:
|
|
|
|
- swapfile fixes (vs scrub, activation vs snapshot creation)
|
|
- for other changes see the [https://git.kernel.org/linus/6f3952cbe00b74739f540981d1afe84cd4dac879 pull request]
|
|
|
|
5.13 (Jun 2021)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
User visible improvements
|
|
|
|
- readahead for send, improving run time of full send by 10% and for incremental by 25%
|
|
- make reflinks respect O_SYNC, O_DSYNC and S_SYNC flags
|
|
- export supported sectorsize values in sysfs (currently only page size, more
|
|
once full subpage support lands)
|
|
- more graceful errors and warnings on 32bit systems when logical addresses for
|
|
metadata reach the limit posed by unsigned long in page::index
|
|
|
|
- error: fail mount if there's a metadata block beyond the limit
|
|
- error: new metadata block would be at unreachable address
|
|
- warn when 5/8th of the limit is reached, for 4K page systems it's 10T, for 64K page it's 160T
|
|
|
|
- zoned mode
|
|
|
|
- relocated zones get reset at the end instead of discard
|
|
- automatic background reclaim of zones that have 75%+ of unusable space, the
|
|
threshold is tunable in sysfs
|
|
|
|
Fixes
|
|
|
|
- fix inefficient preemptive reclaim calculations
|
|
- fix exhaustion of the system chunk array due to concurrent allocations
|
|
- fix fallback to no compression when racing with remount
|
|
- fix unmountable seed device after fstrim
|
|
- fix fiemap to print extents that could get misreported due to internal extent
|
|
splitting and logical merging for fiemap output
|
|
- preemptive fix for dm-crypt on zoned device that does not properly advertise zoned support
|
|
|
|
Core changes
|
|
|
|
- add inode lock to synchronize mmap and other block updates (e.g. deduplication, fallocate, fsync)
|
|
- subpage support update: metadata changes now support read and write
|
|
- error handling through out relocation call paths
|
|
- many other cleanups and code simplifications
|
|
- for other changes see the [https://git.kernel.org/linus/55ba0fe059a577fa08f23223991b24564962620f pull request]
|
|
|
|
5.14 (Aug 2021)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Hilights:
|
|
|
|
- new sysfs knob to limit scrub IO bandwidth per device
|
|
- device stats are also available in /sys/fs/btrfs/FSID/devinfo/DEVID/error_stats
|
|
- support cancellable resize and device delete ioctls
|
|
- change how the empty value is interpreted when setting a property, so far we
|
|
have only 'btrfs.compression' and we need to distinguish a reset to defaults
|
|
and setting "do not compress", in general the empty value will always mean
|
|
'reset to defaults' for any other property, for compression it's either 'no'
|
|
or 'none' to forbid compression
|
|
- performance improvements (xattrs, truncate)
|
|
- space handling improvements, preemptive flushing
|
|
- more subpage support preparation
|
|
- for other changes see the [https://git.kernel.org/linus/122fa8c588316aacafe7e5a393bb3e875eaf5b25 pull request]
|
|
|
|
5.15 (Nov 2021)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Features:
|
|
|
|
- fs-verity support, using standard ioctls, backward compatible with read-only
|
|
limitation on inodes with previously enabled fs-verity
|
|
- idmapped mount support
|
|
- make mount with rescue=ibadroots more tolerant to partially damaged trees
|
|
- allow raid0 on a single device and raid10 on two devices, degenerate cases
|
|
but might be useful as an intermediate step during conversion to other
|
|
profiles
|
|
- zoned mode block group auto reclaim can be disabled via sysfs knob
|
|
|
|
Performance improvements:
|
|
|
|
- continue readahead of node siblings even if target node is in memory, could speed up full send (on sample test +11%)
|
|
- batching of delayed items can speed up creating many files
|
|
- fsync/tree-log speedups
|
|
|
|
- avoid unnecessary work (gains +2% throughput, -2% run time on sample load)
|
|
- reduced lock contention on renames (on dbench +4% throughput, up to -30% latency)
|
|
|
|
Fixes:
|
|
|
|
- various zoned mode fixes
|
|
- preemptive flushing threshold tuning, avoid excessive work on almost full filesystems
|
|
|
|
Core:
|
|
|
|
- continued subpage support, preparation for implementing remaining features
|
|
like compression and defragmentation; with some limitations, write is now
|
|
enabled on 64K page systems with 4K sectors, still considered experimental
|
|
|
|
- no readahead on compressed reads
|
|
- inline extents disabled
|
|
- disabled raid56 profile conversion and mount
|
|
|
|
- improved flushing logic, fixing early ENOSPC on some workloads
|
|
- inode flags have been internally split to read-only and read-write incompat bit parts, used by fs-verity
|
|
- new tree items for fs-verity: descriptor item, Merkle tree item
|
|
- inode operations extended to be namespace-aware
|
|
- cleanups and refactoring
|
|
- for other changes see the [https://git.kernel.org/linus/87045e6546078dae215d1bd3b2bc82b3ada3ca77 pull request]
|
|
|
|
5.16 (Jan 2022)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Related projects: kernel port of zstd 1.4.10 also
|
|
[https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c8c109546a19613d323a319d0c921cb1f317e629
|
|
released] in 5.16
|
|
|
|
Performance related:
|
|
|
|
- misc small inode logging improvements (+3% throughput, -11% latency on sample dbench workload)
|
|
- more efficient directory logging: bulk item insertion, less tree searches and locking
|
|
- speed up bulk insertion of items into a b-tree, which is used when logging
|
|
directories, when running delayed items for directories (fsync and
|
|
transaction commits) and when running the slow path (full sync) of an fsync
|
|
(bulk creation run time -4%, deletion -12%)
|
|
|
|
Core:
|
|
|
|
- continued subpage support
|
|
|
|
- make defragmentation work
|
|
- make compression write work
|
|
|
|
- zoned mode
|
|
|
|
- support ZNS (zoned namespaces), zone capacity is number of usable blocks in each zone
|
|
- add dedicated block group (zoned) for relocation, to prevent out of order writes in some cases
|
|
- greedy block group reclaim, pick the ones with least usable space first
|
|
|
|
- preparatory work for send protocol updates
|
|
- error handling improvements
|
|
- cleanups and refactoring
|
|
- for other changes see the [https://git.kernel.org/linus/037c50bfbeb33b4c74e120eef5b8b99d8f025418 pull request]
|
|
|
|
5.17 (Mar 2022)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Features:
|
|
|
|
- make send work with concurrent block group relocation
|
|
- new exclusive operation 'balance paused' to allow adding a device to
|
|
filesystem with paused balance
|
|
- new sysfs file for fsid stored in the per-device directory to help
|
|
distinguish devices when seeding is enabled
|
|
|
|
Performance:
|
|
|
|
- less metadata needed for directory logging, directory deletion is 20-40% faster
|
|
- in zoned mode, cache zone information during mount to speed up repeated
|
|
queries (about 50% speedup)
|
|
- free space tree entries get indexed and searched by size (latency -30%,
|
|
search run time -30%)
|
|
- less contention in tree node locking when inserting a key and no splits are
|
|
needed (files/sec in fsmark improves by 1-20%)
|
|
|
|
Fixes:
|
|
|
|
- defrag rewrite from 5.16 fixed
|
|
- get rid of warning when mounted with flushoncommit
|
|
|
|
Core:
|
|
|
|
- global reserve stealing got simplified and cleaned up in evict
|
|
- more preparatory work for extent tree v2
|
|
- remove readahead framework
|
|
- error handling improvements
|
|
- for other changes see the [https://git.kernel.org/linus/d601e58c5f2901783428bc1181e83ff783592b6b pull request]
|
|
|
|
5.18 (May 2022)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- encoded read/write ioctls, allows user space to read or write raw data
|
|
directly to extents (now compressed, encrypted in the future), will be
|
|
used by send/receive v2 where it saves processing time
|
|
- zoned mode now works with metadata DUP (the mkfs.btrfs default)
|
|
- allow reflinks/deduplication from two different mounts of the same
|
|
filesystem
|
|
- error message header updates:
|
|
|
|
- print error state: transaction abort, other error, log tree errors
|
|
- print transient filesystem state: remount, device replace, ignored
|
|
checksum verifications
|
|
|
|
- tree-checker: verify the transaction id of the to-be-written dirty
|
|
extent buffer
|
|
- fsync speedups
|
|
|
|
- directory logging speedups (up to -90% run time)
|
|
- avoid logging all directory changes during renames (up to -60% run
|
|
time)
|
|
- avoid inode logging during rename and link when possible (up to -60%
|
|
run time)
|
|
- prepare extents to be logged before locking a log tree path
|
|
(throughput +7%)
|
|
- stop copying old file extents when doing a full fsync ()
|
|
- improved logging of old extents after truncate
|
|
|
|
- remove balance v1 ioctl, superseded by v2 in 2012
|
|
|
|
Core, fixes:
|
|
|
|
- continued extent tree v2 preparatory work
|
|
|
|
- disable features that won't work yet
|
|
- add wrappers and abstractions for new tree roots
|
|
|
|
- prevent deleting subvolume with active swapfile
|
|
- remove device count in superblock and its item in one transaction so
|
|
they cant't get out of sync
|
|
- for subpage, force the free space v2 mount to avoid a warning and
|
|
make it easy to switch a filesystem on different page size systems
|
|
- export sysfs status of exclusive operation 'balance paused', so the
|
|
user space tools can recognize it and allow adding a device with
|
|
paused balance
|
|
|
|
5.19 (Jul 2022)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Features:
|
|
|
|
- subpage:
|
|
|
|
- support on PAGE_SIZE > 4K (previously only 64K)
|
|
- make it work with raid56
|
|
- prevent remount with v1 space cache
|
|
|
|
- repair super block num_devices automatically if it does not match
|
|
the number of device items
|
|
- defrag can convert inline extents to regular extents, up to now inline
|
|
files were skipped but the setting of mount option max_inline could
|
|
affect the decision logic
|
|
|
|
- zoned:
|
|
|
|
- minimal accepted zone size is explicitly set to 4MiB
|
|
- make zone reclaim less aggressive and don't reclaim if there are
|
|
enough free zones
|
|
- add per-profile sysfs tunable of the reclaim threshold
|
|
|
|
- allow automatic block group reclaim for non-zoned filesystems, with
|
|
sysfs tunables
|
|
- tree-checker: new check, compare extent buffer owner against owner
|
|
rootid
|
|
|
|
Performance:
|
|
|
|
- avoid blocking on space reservation when doing nowait direct io
|
|
writes, (+7% throughput for reads and writes)
|
|
- NOCOW write throughput improvement due to refined locking (+3%)
|
|
- send: reduce pressure to page cache by dropping extent pages right
|
|
after they're processed
|
|
|
|
4.x
|
|
---
|
|
|
|
4.0 (Apr 2015)
|
|
^^^^^^^^^^^^^^
|
|
|
|
- file creation time is stored (no easy interface to read it yet)
|
|
- fsync and log replay fixes
|
|
- lots of cleanups and other fixes
|
|
|
|
4.1 (Jun 2015)
|
|
^^^^^^^^^^^^^^
|
|
|
|
Fixes:
|
|
|
|
- regression in chunk removal, conversion to raid1 possible again
|
|
- log tree corruption fix with ''-o discard'' mount
|
|
- bare xattr namespace attribute is not accepted
|
|
- orphan cleanup is started for implicitly mounted default subvolume
|
|
- send fixes
|
|
- cloning within same file
|
|
- EXTENT_SAME ioctl infinite loop fix
|
|
- avoid more ENOSPC in delayed-iput context
|
|
- a few ENOMEM fixes
|
|
- 'automatic empty block group removal' fixups
|
|
|
|
Speedups:
|
|
|
|
- large file deletion: run delayed refs more often
|
|
- large file deletion: don't build up too much work from crc
|
|
- transaction commit latency improved
|
|
- block group cache writeout
|
|
|
|
Qgroup:
|
|
|
|
- limits are shared upon snapshot
|
|
- allow to remove qgroup which has parent but no child
|
|
- fix status of qgroup consistency after rescan
|
|
- fix quota status bits after dsiabling
|
|
- mark qgroups inconsistent after assign/delete actions
|
|
- code cleanups
|
|
|
|
4.2 (Aug 2015)
|
|
^^^^^^^^^^^^^^
|
|
|
|
Enhancements:
|
|
|
|
- transaction abort now reports the caller, not the helper function
|
|
- INO_LOOKUP ioctl: unprivileged if used to just get the rootid (aka. subvolume id)
|
|
- unified ''subvol='' and ''subvolid='' mounting, show the mounted subvol in
|
|
mount options; also, ''/proc/self/mountinfo'' now always correctly shows the
|
|
mounted subvolume
|
|
- reworked internal qgroup logic
|
|
- send: use received_uuid of parent during send
|
|
- sysfs: preparatory works for exporting more stats about devices
|
|
- deduplication on the same inode works
|
|
- deduplication does not change mtime/ctime
|
|
|
|
Fixes:
|
|
|
|
- in send: cloning, renames, orphans
|
|
- few more ENOSPC fixes in case of block group creation/removal
|
|
- fix hang during inode eviction due to concurrent readahead
|
|
- EXTENT_SAME ioctl: handle unaligned length
|
|
- more fixes around automatic block group removal
|
|
- deadlock with EXTENT_SAME and readahead
|
|
- for feature NO_HOLES: fsync, truncate
|
|
|
|
4.3 (Nov 2015)
|
|
^^^^^^^^^^^^^^
|
|
|
|
- fix raid56 rebuild with missing device
|
|
- discard ioctl will return the number of bytes
|
|
- more bugfixes and cleanups
|
|
|
|
4.4 (Jan 2016)
|
|
^^^^^^^^^^^^^^
|
|
|
|
- send fixes: cloning, sending with parent
|
|
- improved handling of framgented space using bitmaps
|
|
- new mount option for debugging: fragment=data|metadata|all
|
|
- updated balance filters: limit, stripes, usage
|
|
- more bugfixes and cleanups
|
|
|
|
4.5 (Mar 2016)
|
|
^^^^^^^^^^^^^^
|
|
|
|
- free space cache v2: an incompat feature to track the free space cache as a b-tree
|
|
- balance:
|
|
- '-dconvert=dup' supported
|
|
- continue but warn if metadata have lower redundancy than data
|
|
- fix: trim does not overwrite bootloader area (introduced in 4.3, fixed in 4.4.x stable kernels)
|
|
- assorted bugfixes, improvements or cleanups
|
|
|
|
4.6 (May 2016)
|
|
^^^^^^^^^^^^^^
|
|
|
|
- mount options:
|
|
|
|
- usebackuproot - replace 'recovery' (works but is deprecated)
|
|
- logreplay, nologreplay - disable log replay at mount time, does no writes to the device
|
|
- norecovery - synthetic option to disable recovery at mount time and disable
|
|
writes (now does: nologreplay)
|
|
|
|
- default inline limit is now 2048 (instead of page size, usually 4096)
|
|
- /dev/btrfs-control now understands the GET_SUPPORTE_FEATURES ioctl
|
|
- get rid of harmless message "''could not find root %llu''"
|
|
- preparatory work for subpage-blocksize patchset
|
|
- fix bug when using overlayfs
|
|
- fixes in readahead, log replay, fsync, and more
|
|
|
|
4.7 (Jul 2016)
|
|
^^^^^^^^^^^^^^
|
|
|
|
- allow balancing to dup with multi-device
|
|
- device deletion by id (additionally to by path)
|
|
- renameat2: add support for RENAME_EXCHANGE and RENAME_WHITEOUT
|
|
- enhanced selftests
|
|
- more preparatory work for "blocksize < page size"
|
|
- more validation checks of superblock (discovered by fuzzing)
|
|
- advertise which crc32c implementation is being used at module load
|
|
- fixed space report by ''df'' with mixed block groups
|
|
- log replay fixes
|
|
- device replace fixes
|
|
|
|
4.8 (Oct 2016)
|
|
^^^^^^^^^^^^^^
|
|
|
|
- space reservations and handling uses ticketed system, this should improve
|
|
latency and fairness in case when there are several threads blocked on
|
|
flushing
|
|
- fixes of bugs triggered by fuzzed images
|
|
- global ratelmit of all printed messages
|
|
- several send, qgroup fixes
|
|
- cleanups
|
|
|
|
4.9 (Dec 2016)
|
|
^^^^^^^^^^^^^^
|
|
|
|
- improved performance of extent sharing detection in FIEMAP
|
|
|
|
Fixes:
|
|
|
|
- device delete hang at the end of the operation
|
|
- free space tree bitmap endianity fixed on big-endian machines
|
|
- parallel incremental send and balance issue fixed
|
|
- cloning ioctl can be interrupted by a fatal signal
|
|
- other stability fixes or cleanups
|
|
|
|
4.10 (Feb 2017)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- balance: human readable block group descripion in the log
|
|
- balance: fix storing of stripes_min, stripes_max filters to the on-disk item
|
|
- qgroup: fix accounting bug during concurrent balance run
|
|
- better worker thread resource limit checks
|
|
- fix ENOSPC during hole punching
|
|
- fix ENOSPC when reflinking a heavily fragmented file
|
|
- fix crash when certain tracepoints are enabled
|
|
- fix compat ioctl calls on non-compat systems
|
|
- improved delayed ref iteration performance
|
|
- many cleanups
|
|
|
|
4.11 (May 2017)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- mostly a cleanup release
|
|
- improved csum mismatch messages
|
|
- move some qgroup work out of transaction commit
|
|
- let unlink temporarily exceed quotas
|
|
- fix truncate and lockless DIO writes
|
|
- incremental send fixes
|
|
- fix remount using ssd and nossd combinations
|
|
|
|
4.12 (Jul 2017)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- new tracepoints: file item
|
|
- fix qgoup accounting when inode_cache is in use
|
|
- fix incorrect number report in stat::t_blocks under certain conditions
|
|
- raid56 fixes:
|
|
|
|
- enable auto-repair during read (ie. similar to what raid1 and raid10 do)
|
|
- fix potential crash with concurrent scrub and dev-replace
|
|
- fix potential crash when cancelling dev-replace
|
|
- fix false reports during scrub when it's possible to do repair
|
|
- fix wrong mirror report during repair
|
|
|
|
- many cleanups
|
|
|
|
4.13 (Sep 2017)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- deprecated: mount option ''alloc_start''
|
|
- qgroups: new sysctl to allow temporary quota override with CAP_SYS_RESOURCE
|
|
- statx syscall support
|
|
- nowait AIO support
|
|
- lots of cleanups around bio processing and error handling
|
|
- memory allocation constraint cleanups and improvements
|
|
- more sanity checks (for dir_item)
|
|
- compression will be skipped if there's no improvement (at least one block)
|
|
- fix invalid extent maps due to hole punching
|
|
- fix: sgid not cleared when changing acls
|
|
- some enospc corner case fixes
|
|
- send fixes
|
|
- other cleanups
|
|
|
|
4.14 (Nov 2017)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- added zstd compression
|
|
- fine-grained check for degraded mount (verify raid constraints on chunk level, not device level)
|
|
- userspace transaction ioctl has been deprecated, scheduled for removal in 4.17
|
|
- foundation code for compression heuristics
|
|
- mount option 'ssd' does not force block allocation alignments
|
|
|
|
Fixes:
|
|
|
|
- potential raid repair and compression crash
|
|
- prevent to set invalid default subvolid
|
|
- resume qgroup rescan on rw remount
|
|
- better reporting of detected checksum mismatches for DIO
|
|
- compression for defrag vs per-file behaves as expected, respecting the requested value
|
|
- possible deadlock with readdir and pagefault
|
|
- emission of invalid clone operations in send
|
|
- cleanups and refactoring
|
|
|
|
4.15 (Jan 2018)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
New features:
|
|
|
|
- extend mount options to specify zlib compression level, <i>-o compress=zlib:9</i>
|
|
- v2 of ioctl "extent to inode mapping"
|
|
- populate compression heuristics logic
|
|
- enable indexing for btrfs as lower filesystem in overlayfs
|
|
- speedup page cache readahead during send on large files
|
|
|
|
Internal changes:
|
|
|
|
- more sanity checks of b-tree items when reading them from disk
|
|
- more EINVAL/EUCLEAN fixups, missing BLK_STS_* conversion, other errno or error handling fixes
|
|
- remove some homegrown IO-related logic, that's been obsoleted by core block
|
|
layer changes (batching, plug/unplug, own counters)
|
|
- add ref-verify, optional debugging feature to verify extent reference accounting
|
|
- simplify code handling outstanding extents, make it more clear where and how the accounting is done
|
|
- make delalloc reservations per-inode, simplify the code and make the logic more straightforward
|
|
- extensive cleanup of delayed refs code
|
|
- fix send ioctl on 32bit with 64bit kernel
|
|
|
|
4.16 (Apr 2018)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- fallocate: implement zero range mode
|
|
- avoid losing data raid profile when deleting a device
|
|
- tree item checker: more checks for directory items and xattrs
|
|
- raid56 recovery: don't use cached stripes, that could be potentially changed
|
|
and a later RMW or recovery would lead to corruptions or failures
|
|
- let raid56 try harder to rebuild damaged data, reading from all stripes if necessary
|
|
- fix scrub to repair raid56 in a similar way as in the case above
|
|
- cleanups: device freeing, removed some call indirections, redundant
|
|
bio_put/_get, unused parameters, refactorings and renames
|
|
- RCU list traversal fixups
|
|
- simplify mount callchain, remove recursing back when mounting a subvolume
|
|
- plug for fsync, may improve bio merging on multiple devices
|
|
- compression heuristic: replace heap sort with radix sort, gains some performance
|
|
- add extent map selftests, buffered write vs dio
|
|
- see [https://git.kernel.org/linus/31466f3ed710e5761077190809e694f55aed5deb pull request]
|
|
|
|
4.17 (Jun 2018)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- mount options: new nossd_spread; subvolid will detect junk after the number and fail the mount
|
|
- add message after cancelled device replace
|
|
- direct module dependency on libcrc32, removed own crc wrappers
|
|
- removed user space transaction ioctls
|
|
- use lighter locking when reading /proc/self/mounts (RCU)
|
|
- skip writeback of last page when truncating file to same size
|
|
- send: do not issue unnecessary truncate operations
|
|
- selftests: more tree block validation
|
|
- fix fsync after hole punching when using no-holes feature
|
|
- raid56:
|
|
|
|
- make sure target is identical to source when raid56 rebuild fails after dev-replace
|
|
- faster rebuild during scrub, batch by stripes and not block-by-block
|
|
- make more use of cached data when rebuilding from a missing device
|
|
|
|
- [https://git.kernel.org/linus/94514bbe9e5c402c4232af158a295a8fdfd72a2c pull request]
|
|
|
|
4.18 (Aug 2018)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
- added support for the ioctl FS_IOC_FSGETXATTR, per-inode flags, successor of
|
|
GET/SETFLAGS; now supports only existing flags: append, immutable, noatime,
|
|
nodump, sync
|
|
- 3 new unprivileged ioctls to allow users to enumerate subvolumes
|
|
- dedupe syscall implementation does not restrict the range to 16MiB, though it still splits the whole range to 16MiB chunks
|
|
- on user demand, rmdir() is able to delete an empty subvolume, export the capability in sysfs
|
|
- fix inode number types in tracepoints, other cleanups
|
|
- send: improved speed when dealing with a large removed directory,
|
|
measurements show decrease from 2000 minutes to 2 minutes on a directory
|
|
with 2 million entries
|
|
- pre-commit check of superblock to detect a mysterious in-memory corruption
|
|
- log message updates
|
|
- [https://git.kernel.org/linus/704996566f97e0e24c97052f81678060c213c260 pull request]
|
|
|
|
4.19 (Oct 2018)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Hilights, no big changes in this releaase:
|
|
|
|
- allow defrag on opened read-only files that have rw permissions
|
|
- tree checker improvements, reported by fuzzing
|
|
- send, fix incorrect file layout after hole punching beyond eof
|
|
- reset on-disk device stats value after replace
|
|
- assorted fixes, cleanups and dead code removal
|
|
- [https://git.kernel.org/linus/318b067a5dd649d198c2ba00cf7408d778fc00b4 pull request]
|
|
|
|
4.20 (Dec 2018)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
Performance improvements:
|
|
|
|
- fewer wakeups and blocking during b-tree traversals, improved latencies and scalability
|
|
- qgroups: 30+% run time improvement during balance, no accounting on unchanged subtrees (continued)
|
|
- use a cached variant of rb-tree, speeds up traversal in some cases
|
|
|
|
Fixes:
|
|
|
|
- trim:
|
|
|
|
- could miss some block groups, if logical offset was too high and did not fit the range
|
|
- better error reporting, continue as far as possible
|
|
- less interaction with transaction commit
|
|
|
|
- fsync: fix log replay and O_TMPFILE warnings
|
|
- qgroups: fix rescan that might misc some dirty groups
|
|
- don't clean dirty pages during buffered writes, this could lead to lost updates in some corner cases
|
|
- some block groups could have been delayed in creation, if the allocation triggered another one
|
|
- error handling improvements
|
|
- other cleanups and refactoring
|
|
- [https://git.kernel.org/linus/a1a4f841ec4585185c0e75bfae43a18b282dd316 pull request]
|
|
|
|
3.x
|
|
---
|
|
|
|
3.0 (Jul 2011)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* Filesystem scrub
|
|
* Auto-defragmentation (autodefrag mount option)
|
|
* Improved block allocator
|
|
* Sped up file creation/deletion by delayed operation
|
|
|
|
3.1 (Oct 2011)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* Stability fixes (lots of them, really), notably fixing early ENOSPC, improved
|
|
handling of a few error paths and corner cases, fix for the crash during log
|
|
replay.
|
|
|
|
3.2 (Jan 2012)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* Log of past roots to aid recovery (option ''recovery'')
|
|
* Subvolumes mountable by full path
|
|
* Added ''nospace_cache'' option
|
|
* Lots of space accounting fixes
|
|
* Improved scrub performance thanks to new read-ahead infrastructure
|
|
* Scrub prints paths of corrupted files
|
|
* ioctl for resolving logical->inode and inode->path
|
|
* Integrated raid-repair (if possible)
|
|
* Data corruption fix for parallel snapshot creation
|
|
* Write barriers for multiple devices were fixed to be more resistant in case of power failure
|
|
|
|
3.3 (Mar 2012)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* restriper - infrastructure to change btrfs raid profiles on the fly via balance
|
|
* optional integrity checker infrastructure ([http://lwn.net/Articles/466493/ details])
|
|
* fixed a few corner cases where TRIM did not process some blocks
|
|
* cluster allocator improvements (less fragmentation, some speedups)
|
|
|
|
3.4 (May 2012)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* Allow metadata blocks larger than the page size (4K). This allows metadata
|
|
blocks up to 64KB in size. In practice 16K and 32K seem to work best. For
|
|
workloads with lots of metadata, this cuts down the size of the extent
|
|
allocation tree dramatically and fragments much less. (Chris Mason)
|
|
* Improved error handling (IO errors). This gives Btrfs the ability to abort
|
|
transactions and go read-only on errors other than internal logic errors and
|
|
ENOMEM more gracefully instead of crashing. (Jeff Mahoney)
|
|
* Reworked the way in which metadata interacts with the page cache.
|
|
page->private now points to the btrfs extent_buffer object, which makes
|
|
everything faster. The code was changed so it now writes a whole extent
|
|
buffer at a time instead of allowing individual pages to go down. It is now
|
|
more aggressive about dropping pages for metadata blocks that were freed due
|
|
to COW. Overall, metadata caching is much faster now. (Josef Bacik)
|
|
|
|
3.5 (Jun 2012)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* collect device statistics (read/write failures, checksum errors, corrupted blocks)
|
|
* integrity checker (3.3+) supports bigblocks (3.4+)
|
|
* more friendly NFS support (native ''i_version'')
|
|
* ''thread_pool'' mount option tunable via remount
|
|
* ''fsync'' speed improvements
|
|
* several fixes related to read-only mounts
|
|
* scrub thread priority lowered to idle
|
|
* preparatory works for 3.6 features (''tree_mod_log'')
|
|
|
|
3.6 (Sep 2012)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* subvolume-aware quotas (''qgroups'')
|
|
* support for send/receive between snapshot changes ([http://lwn.net/Articles/506244/ LWN article])
|
|
* ''atime'' is not updated on read-only snapshots ([http://lwn.net/Articles/499293/ LWN article])
|
|
* allowed cross-subvolume file clone (aka. reflink)
|
|
* remount with ''no'' compression possible
|
|
* new ioctl to read device readiness status
|
|
* speed improvement for concurrent multithreaded reads
|
|
|
|
3.7 (Dec 2012)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* ''fsync'' speedups
|
|
* removed limitation of number of hardlinks in a single directory
|
|
* file hole punching ([http://lwn.net/Articles/415889/ LWN article])
|
|
* per-file ''NOCOW''
|
|
* fixes to send/receive
|
|
|
|
3.8 (Feb 2013)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* ability to replace devices at runtime in an effective way ([http://lwn.net/Articles/524589/ description])
|
|
* speed improvements (cumulative effect of many small improvements)
|
|
* a few more bugfixes
|
|
|
|
3.9 (Apr 2013)
|
|
^^^^^^^^^^^^^^
|
|
|
|
* preliminary Raid 5/6 support (details in the [http://www.spinics.net/lists/linux-btrfs/msg22169.html announcement])
|
|
* snapshot-aware defrag
|
|
* a mode of ''send'' to avoid transferring file data
|
|
* direct IO speedup ([https://patchwork.kernel.org/patch/2114921/ numbers])
|
|
* new ''ioctl''s to set/get filesystem label
|
|
* defrag is cancellable
|
|
|
|
3.10 (Jun 2013)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* reduced size of metadata by so-called '''[[Feature:Skinny_Metadata|skinny extents]]''' [http://git.kernel.org/linus/3173a18f70554fe7880bb2d85c7da566e364eb3c]
|
|
* enhanced syslog message format [http://permalink.gmane.org/gmane.comp.file-systems.btrfs/24330]
|
|
* the mount option ''subvolrootid'' is deprecated
|
|
* lots of stability improvements, removed <big>many</big> <small>BUG_ONs</small> <!-- a big thing! -->
|
|
* qgroups are automatically created when quotas are enabled [http://git.kernel.org/linus/7708f029dca5f1b9e9d6ea01ab10cd83e4c74ff2]
|
|
* qgroups are able to ''rescan'' current filesystem and sync the quota state with the existing subvolumes
|
|
* enhanced ''send/recv '' format for multiplexing more data into one stream [http://git.kernel.org/linus/c2c71324ecb471c932bc1ff59e46ffcf82f274fc]
|
|
* various unsorted code cleanups, minor performance updates
|
|
|
|
3.11 (Sep 2013)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* extent cloning within one file
|
|
* ioctl to wait for quota rescan completion
|
|
* device deletion returns error code to userspace (not in syslog anymore)
|
|
* usual load of small fixes and improvements
|
|
|
|
3.12 (Nov 2013)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* Major performance improvement for send/receive with large numbers of subvolumes
|
|
* Support for batch [[deduplication]] (userspace tools required)
|
|
* new mount option ''commit'' to set the commit interval
|
|
* Lots of stability and bugfix patches
|
|
|
|
3.13 (Jan 2014)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* ''fiemap'' exports information about shared extents
|
|
* bugfix and stability foucsed release
|
|
|
|
3.14 (Mar 2014)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* optional incompat disk format improvement aiming at speedup, removing file hole representation, named ''no-holes''
|
|
* ioctl to query/change feature bits (e.g. switching on extended refs on-line now possible)
|
|
* export filesystem info through sysfs: features, allocation profiles
|
|
* added pairing mount options (for remount)
|
|
* heap of small performance optimizations
|
|
* snapshot-aware defrag was disabled due to problems
|
|
|
|
3.15 (Jun 2014)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* pile of ''send'' fixes (stability, speed)
|
|
* worker threads now use kernel workqueues
|
|
|
|
3.16 (Aug 2014)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* ''O_TMPFILE'' support [http://kernelnewbies.org/Linux_3.11#head-8be09d59438b31c2a724547838f234cb33c40357]
|
|
* reworked qgroup accounting, to fix negative numbers after subvol deletion
|
|
* SEARCH_TREE ioctl v2, extended for retrieving more data [http://www.spinics.net/lists/linux-btrfs/msg31213.html]
|
|
* new balance filter ''limit'' for more finegrained balancing [http://www.spinics.net/lists/linux-btrfs/msg33872.html]
|
|
* ioctl FS_INFO and it's sysfs counterpart export information about ''nodesize'', ''sectorsize'' and ''clone_alignment''
|
|
* snapshots are protected during send
|
|
|
|
3.17 (Oct 2014)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* fix for the infamous deadlock [https://git.kernel.org/linus/9e0af23764344f7f1b68e4eefbe7dc865018b63d]
|
|
* fixed longstanding bug in qgroups accounting after snapshot deletion [https://git.kernel.org/linus/1152651a081720ef6a8c76bb7da676e8c900ac30]
|
|
* updated (less inaccurate) ''df'' numbers [https://git.kernel.org/linus/ba7b6e62f420f5a8832bc161ab0c7ba767f65b3d]
|
|
* speedup for ''rename'' and ''truncate'', less strict flushes [https://git.kernel.org/linus/8d875f95da43c6a8f18f77869f2ef26e9594fecc]
|
|
* updated and fixes to the ''seeding'' feature
|
|
|
|
3.17 (Oct 2014)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* fix for the infamous deadlock [https://git.kernel.org/linus/9e0af23764344f7f1b68e4eefbe7dc865018b63d]
|
|
* fixed longstanding bug in qgroups accounting after snapshot deletion [https://git.kernel.org/linus/1152651a081720ef6a8c76bb7da676e8c900ac30]
|
|
* updated (less inaccurate) ''df'' numbers [https://git.kernel.org/linus/ba7b6e62f420f5a8832bc161ab0c7ba767f65b3d]
|
|
* speedup for ''rename'' and ''truncate'', less strict flushes [https://git.kernel.org/linus/8d875f95da43c6a8f18f77869f2ef26e9594fecc]
|
|
* updated and fixes to the ''seeding'' feature
|
|
|
|
3.18 (Dec 2014)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
3.19 (Feb 2015)
|
|
^^^^^^^^^^^^^^^
|
|
|
|
* raid56 supports scrub and device replace
|
|
|
|
2.6.x
|
|
-----
|
|
|
|
2.6.39 (May 2011)
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
Per-file compression and NOCOW control. Support for bulk TRIM on SSDs.
|
|
|
|
2.6.38 (March 2011)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
Added LZO compression method, FIEMAP bugfixes with delalloc, subvol flags
|
|
get/set ioctl, allow compression during defrag.
|
|
|
|
2.6.37 (January 2011)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
On-disk free space cache, asynchronous snapshots, unprivileged subvolume
|
|
deletion, extent buffer switches from a rbtree with spinlocks to a radix tree
|
|
with RCU. (Explanations of these features are described in
|
|
[http://www.linux-mag.com/id/7945 this] article [registration needed]).
|
|
|
|
2.6.35 (August 2010)
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Direct I/O support and -ENOSPC handling of volume management operations,
|
|
completing the -ENOSPC support.
|
|
|
|
2.6.34 (May 2010)
|
|
^^^^^^^^^^^^^^^^^
|
|
|
|
Support for changing the default subvolume, a new userspace tool (btrfs), an
|
|
ioctl that lists all subvolumes, an ioctl to allow improved df math, and other
|
|
improvements.
|
|
|
|
2.6.33 (February 2010)
|
|
^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Some minor -ENOSPC improvements.
|
|
|
|
2.6.32 (December 2009)
|
|
^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
ENOSPC
|
|
|
|
Btrfs has not had serious -ENOSPC ("no space") handling, the COW oriented
|
|
design makes handling such situations more difficult than filesystems that just
|
|
rewrite the blocks. In this release Josef Bacik (Red Hat) has added the
|
|
necessary infrastructure to fix that problem. Note: The filesystem may run out
|
|
of space and still show some free space. That space comes from a data/metadata
|
|
chunk that can't get filled because there's not space left to create its
|
|
metadata/data counterpart chunk. This is unrelated to the -ENOSPC handling and
|
|
will be fixed in the future. Code:
|
|
[http://git.kernel.org/linus/9ed74f2dba6ebf9f30b80554290bfc73cc3ef083 (commit)]
|
|
|
|
Proper snapshot and subvolume deletion
|
|
|
|
In the last btrfs-progs version you have options that allow to delete snapshots
|
|
and subvolumes without having to use rm. This is much faster because it does
|
|
the deletion via btree walking. It's also now possible to rename snapshots and
|
|
subvols. Work done by Yan Zheng (Oracle). Code:
|
|
[http://git.kernel.org/linus/4df27c4d5cc1dda54ed7d0a8389347f2df359cf9 (commit
|
|
1)], [http://git.kernel.org/linus/76dda93c6ae2c1dc3e6cde34569d6aca26b0c918 2)]
|
|
|
|
Performance improvements
|
|
|
|
Streaming writes on very fast hardware were previously CPU bound at around
|
|
400MB/s. Chris Mason (Oracle) has improved the code so that now it can push
|
|
over 1GB/s while using the same CPU as XFS (factoring out checksums). There are
|
|
also improvements for writing large portions of extents, and other workloads.
|
|
Multidevice setups are also much faster due to the per-BDI writeback changes.
|
|
The performance of fsync() was greatly improved, which fixed a severe slowdown
|
|
while using yum in Fedora 11.
|
|
|
|
Support for "discard" operation on SSD devices
|
|
|
|
"Discard" support is a way to telling SSD devices which blocks are free so that
|
|
the underlying firmware knows that it's safe to do some optimizations
|
|
[http://git.kernel.org/linus/e244a0aeb6a599c19a7c802cda6e2d67c847b154
|
|
(commit)],
|
|
[http://git.kernel.org/linus/0634857488ec6e28fa22920cd0bee3c2ac07ccfd (commit)]
|
|
|
|
0.x
|
|
---
|
|
|
|
0.13 and older
|
|
^^^^^^^^^^^^^^
|
|
|
|
* Copy on write FS
|
|
* Checksumming
|
|
* Transactions
|
|
* Snapshotting
|
|
* Subvolumes
|
|
|
|
0.14 (April 30, 2008)
|
|
^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
* Support for multiple devices
|
|
* raid0, raid1 and raid10, single spindle metadata duplication
|
|
|
|
0.15 (May 29, 2008)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
* Metadata back references
|
|
* Online growing and shrinking
|
|
* Conversion program from Ext3
|
|
* data=ordered support
|
|
* COW-free data writes.
|
|
* focus on stability fixes for the multiple device code
|
|
|
|
0.16 (August 2008)
|
|
^^^^^^^^^^^^^^^^^^
|
|
|
|
v0.16 does change the disk format from v0.15, and it includes a long list of
|
|
performance and stability updates.
|
|
|
|
Fine grained Btree locking
|
|
|
|
Locking is now done in a top down fashion while searching the btree, and higher
|
|
level locks are freed when they are no longer required. Extent allocations
|
|
still have a coarse grained lock, but that will be improved in the next
|
|
release.
|
|
|
|
Improved data=ordered
|
|
|
|
Ordered data mode loosely means any system that prevents garbage or stale data
|
|
blocks after a crash. It was previously implemented the same way ext3 does it,
|
|
which is to force pending data writes down before a transaction commits.
|
|
|
|
The data=ordered code was changed to only modify metadata in the btree after
|
|
data extents are fully written on disk. This allows a transaction commit to
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proceed without waiting for all the data writes on the FS to finish.
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|
|
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A single fsync or synchronous write no longer forces all the dirty data on the
|
|
FS to disk, as it does in ext3 and reiserfsv3.
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|
|
|
Although it is not implemented yet, the new data=ordered code would allow
|
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atomic writes of almost any size to a single file to be exported to userland.
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|
|
|
ACL support (Josef Bacik)
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|
|
|
ACLs are implemented and enabled by default.
|
|
|
|
Lost file prevention (Josef Bacik)
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|
|
|
The VFS and posix APIs force filesystems allow files to be unlinked from a
|
|
directory before they are deleted from the FS. If the system crashes between
|
|
the unlink and the deletion, the file is still consuming space on disk, but not
|
|
listed in any directory.
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|
|
|
Btrfs now tracks these files and makes sure they are reclaimed if the system
|
|
crashes before they are fully deleted.
|
|
|
|
New directory index format (Josef Bacik)
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|
|
|
Btrfs indexes directories in two ways. The first index allows fast name
|
|
lookups, and the second is optimized to return inodes in something close to
|
|
disk order for readdir. The second index is an important part of good
|
|
performance for full filesystem backups.
|
|
|
|
A per-directory sequence number is now used for the second index, removing some
|
|
worst case conditions around files that are hard linked into the same directory
|
|
many times.
|
|
|
|
Faster unmount times (Yan Zheng)
|
|
|
|
Btrfs waits for old transactions to be completely removed from the FS before
|
|
unmount finishes. A new reference count cache was added to make this much less
|
|
IO intensive, improving FS performance in all workloads.
|
|
|
|
Improved streaming reads and writes
|
|
|
|
The new data=ordered code makes streaming writes much faster. Streaming reads
|
|
are improved by tuning the thread pools used to process data checksums after
|
|
the read is done. On machines with sufficient CPU power to keep up with the
|
|
disks, data checksumming is able to run as fast as nodatasum mounts.
|
|
|
|
0.17 (January 2009)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
Btrfs is now in 2.6.29-rc1!
|
|
|
|
v0.17 has a new disk format since v0.16. Future releases will try to maintain
|
|
backwards compatibility with this new format.
|
|
|
|
Compression
|
|
|
|
Transparent zlib compression of file data is enabled by mount -o compress.
|
|
|
|
Improved block allocation routines (Josef Bacik)
|
|
|
|
Many performance problems in the allocator are addressed in this release
|
|
|
|
Improved block sharing while moving extents (Yan Zheng)
|
|
|
|
The btrfs-vol commands to add, remove and balance space across devices triggers
|
|
a COW of metadata and data blocks. This release is much better at maintaining
|
|
shared blocks between snapshots when that COW happens.
|
|
|
|
Seed Device support
|
|
|
|
It is now possible to create a filesystem to seed other Btrfs filesystems. The
|
|
original filesystem and devices are included as a readonly starting point to
|
|
the new FS. All modifications go onto different devices and the COW machinery
|
|
makes sure the original is unchanged.
|
|
|
|
Many bug fixes and performance improvements
|
|
|
|
0.18 (January 2009)
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
v0.18 has the same disk format as 0.17, but a bug was found in the ioctl
|
|
interface shared between 32 bit and 64 bit programs. This was fixed by changing
|
|
the ioctl interface. Anyone using 2.6.29-rc2 will need to update to v0.18 of
|
|
the btrfs progs.
|
|
|
|
There is no need to reformat though, the disk format is still compatible.
|
|
|
|
0.19 (June 2009)
|
|
^^^^^^^^^^^^^^^^
|
|
|
|
v0.19 is a forward rolling format change, which means that it can read the
|
|
v0.18 disk format but older kernels and older btrfs-progs code will not be able
|
|
to read filesystems created with v0.19. The new code changes the way that
|
|
extent back references are recorded, making them significantly more efficient.
|
|
In general, v0.19 is a dramatic speed improvement over v0.18 in almost every
|
|
workload.
|
|
|
|
The v0.19 utilities are meant for use with kernels 2.6.31-rc1 and higher. Git
|
|
trees are available with the new format code for 2.6.30 kernels, please see the
|
|
download section for details.
|
|
|
|
If you do not wish to roll forward to the new disk format, use the v0.18 utilities.
|