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Diffstat (limited to 'Documentation/admin-guide/device-mapper/writecache.rst')
| -rw-r--r-- | Documentation/admin-guide/device-mapper/writecache.rst | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/Documentation/admin-guide/device-mapper/writecache.rst b/Documentation/admin-guide/device-mapper/writecache.rst index 65427d8dfca6..60c16b7fd5ac 100644 --- a/Documentation/admin-guide/device-mapper/writecache.rst +++ b/Documentation/admin-guide/device-mapper/writecache.rst @@ -20,6 +20,7 @@ Constructor parameters: size) 5. the number of optional parameters (the parameters with an argument count as two) + start_sector n (default: 0) offset from the start of cache device in 512-byte sectors high_watermark n (default: 50) @@ -74,17 +75,28 @@ Constructor parameters: the origin volume in the last n milliseconds Status: + 1. error indicator - 0 if there was no error, otherwise error number 2. the number of blocks 3. the number of free blocks 4. the number of blocks under writeback +5. the number of read blocks +6. the number of read blocks that hit the cache +7. the number of write blocks +8. the number of write blocks that hit uncommitted block +9. the number of write blocks that hit committed block +10. the number of write blocks that bypass the cache +11. the number of write blocks that are allocated in the cache +12. the number of write requests that are blocked on the freelist +13. the number of flush requests +14. the number of discarded blocks Messages: flush - flush the cache device. The message returns successfully + Flush the cache device. The message returns successfully if the cache device was flushed without an error flush_on_suspend - flush the cache device on next suspend. Use this message + Flush the cache device on next suspend. Use this message when you are going to remove the cache device. The proper sequence for removing the cache device is: @@ -98,3 +110,5 @@ Messages: 6. the cache device is now inactive and it can be deleted cleaner See above "cleaner" constructor documentation. + clear_stats + Clear the statistics that are reported on the status line |