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author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-08 11:51:05 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-08 11:51:05 -0700 |
commit | ebb37277796269da36a8bc5d72ed1e8e1fb7d34b (patch) | |
tree | 0ded627a62a5cec70b18d12825dd858855c135d3 /Documentation/ABI/testing/sysfs-block-bcache | |
parent | 4de13d7aa8f4d02f4dc99d4609575659f92b3c5a (diff) | |
parent | f50efd2fdbd9b35b11f5778ed85beb764184bda9 (diff) |
Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
"It might look big in volume, but when categorized, not a lot of
drivers are touched. The pull request contains:
- mtip32xx fixes from Micron.
- A slew of drbd updates, this time in a nicer series.
- bcache, a flash/ssd caching framework from Kent.
- Fixes for cciss"
* 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits)
bcache: Use bd_link_disk_holder()
bcache: Allocator cleanup/fixes
cciss: bug fix to prevent cciss from loading in kdump crash kernel
cciss: add cciss_allow_hpsa module parameter
drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions
mtip32xx: Workaround for unaligned writes
bcache: Make sure blocksize isn't smaller than device blocksize
bcache: Fix merge_bvec_fn usage for when it modifies the bvm
bcache: Correctly check against BIO_MAX_PAGES
bcache: Hack around stuff that clones up to bi_max_vecs
bcache: Set ra_pages based on backing device's ra_pages
bcache: Take data offset from the bdev superblock.
mtip32xx: mtip32xx: Disable TRIM support
mtip32xx: fix a smatch warning
bcache: Disable broken btree fuzz tester
bcache: Fix a format string overflow
bcache: Fix a minor memory leak on device teardown
bcache: Documentation updates
bcache: Use WARN_ONCE() instead of __WARN()
bcache: Add missing #include <linux/prefetch.h>
...
Diffstat (limited to 'Documentation/ABI/testing/sysfs-block-bcache')
-rw-r--r-- | Documentation/ABI/testing/sysfs-block-bcache | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-block-bcache b/Documentation/ABI/testing/sysfs-block-bcache new file mode 100644 index 000000000000..9e4bbc5d51fd --- /dev/null +++ b/Documentation/ABI/testing/sysfs-block-bcache @@ -0,0 +1,156 @@ +What: /sys/block/<disk>/bcache/unregister +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + A write to this file causes the backing device or cache to be + unregistered. If a backing device had dirty data in the cache, + writeback mode is automatically disabled and all dirty data is + flushed before the device is unregistered. Caches unregister + all associated backing devices before unregistering themselves. + +What: /sys/block/<disk>/bcache/clear_stats +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + Writing to this file resets all the statistics for the device. + +What: /sys/block/<disk>/bcache/cache +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For a backing device that has cache, a symlink to + the bcache/ dir of that cache. + +What: /sys/block/<disk>/bcache/cache_hits +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For backing devices: integer number of full cache hits, + counted per bio. A partial cache hit counts as a miss. + +What: /sys/block/<disk>/bcache/cache_misses +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For backing devices: integer number of cache misses. + +What: /sys/block/<disk>/bcache/cache_hit_ratio +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For backing devices: cache hits as a percentage. + +What: /sys/block/<disk>/bcache/sequential_cutoff +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For backing devices: Threshold past which sequential IO will + skip the cache. Read and written as bytes in human readable + units (i.e. echo 10M > sequntial_cutoff). + +What: /sys/block/<disk>/bcache/bypassed +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + Sum of all reads and writes that have bypassed the cache (due + to the sequential cutoff). Expressed as bytes in human + readable units. + +What: /sys/block/<disk>/bcache/writeback +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For backing devices: When on, writeback caching is enabled and + writes will be buffered in the cache. When off, caching is in + writethrough mode; reads and writes will be added to the + cache but no write buffering will take place. + +What: /sys/block/<disk>/bcache/writeback_running +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For backing devices: when off, dirty data will not be written + from the cache to the backing device. The cache will still be + used to buffer writes until it is mostly full, at which point + writes transparently revert to writethrough mode. Intended only + for benchmarking/testing. + +What: /sys/block/<disk>/bcache/writeback_delay +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For backing devices: In writeback mode, when dirty data is + written to the cache and the cache held no dirty data for that + backing device, writeback from cache to backing device starts + after this delay, expressed as an integer number of seconds. + +What: /sys/block/<disk>/bcache/writeback_percent +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For backing devices: If nonzero, writeback from cache to + backing device only takes place when more than this percentage + of the cache is used, allowing more write coalescing to take + place and reducing total number of writes sent to the backing + device. Integer between 0 and 40. + +What: /sys/block/<disk>/bcache/synchronous +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For a cache, a boolean that allows synchronous mode to be + switched on and off. In synchronous mode all writes are ordered + such that the cache can reliably recover from unclean shutdown; + if disabled bcache will not generally wait for writes to + complete but if the cache is not shut down cleanly all data + will be discarded from the cache. Should not be turned off with + writeback caching enabled. + +What: /sys/block/<disk>/bcache/discard +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For a cache, a boolean allowing discard/TRIM to be turned off + or back on if the device supports it. + +What: /sys/block/<disk>/bcache/bucket_size +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For a cache, bucket size in human readable units, as set at + cache creation time; should match the erase block size of the + SSD for optimal performance. + +What: /sys/block/<disk>/bcache/nbuckets +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For a cache, the number of usable buckets. + +What: /sys/block/<disk>/bcache/tree_depth +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For a cache, height of the btree excluding leaf nodes (i.e. a + one node tree will have a depth of 0). + +What: /sys/block/<disk>/bcache/btree_cache_size +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + Number of btree buckets/nodes that are currently cached in + memory; cache dynamically grows and shrinks in response to + memory pressure from the rest of the system. + +What: /sys/block/<disk>/bcache/written +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For a cache, total amount of data in human readable units + written to the cache, excluding all metadata. + +What: /sys/block/<disk>/bcache/btree_written +Date: November 2010 +Contact: Kent Overstreet <kent.overstreet@gmail.com> +Description: + For a cache, sum of all btree writes in human readable units. |