table of contents
VDOSTATS(8) | System Manager's Manual | VDOSTATS(8) |
NAME¶
vdostats - Display configuration and statistics of VDO volumes
SYNOPSIS¶
vdostats [OPTION]... [DEVICE]...
DESCRIPTION¶
vdostats displays configuration and statistics information for the given VDO devices. If no devices are given, it displays information about all VDO devices.
OPTIONS¶
- -h, --help
- Show help message and exit
- -a, --all
- This option is only for backwards compatibility. It is now equivalent to --verbose.
- --human-readable
- Display block values in readable form (Base 2: 1 KB = 2^10 bytes = 1024 bytes).
- --si
- Modifies the output of the --human-readable option to use SI units (Base 10: 1 KB = 10^3 bytes = 1000 bytes). If the --human-readable option is not supplied, this option has no effect.
- -v, --verbose
- Displays the utilization and block I/O (bios) statistics for the selected VDO devices.
- -V, --version
- Prints the vdostats version number and exits
OUTPUT¶
The default output format is a table with the following columns, similar to that of the Linux df utility:
- Device
- The path to the VDO volume
- 1K-blocks
- The total number of 1K blocks allocated for a VDO volume (= physical volume size * block size / 1024)
- Used
- The total number of 1K blocks used on a VDO volume (= physical blocks used * block size / 1024)
- Available
- The total number of 1K blocks available on a VDO volume (= physical blocks free * block size / 1024)
- Use%
- The percentage of physical blocks used on a VDO volume (= used blocks / allocated blocks * 100)
- Space Saving%
- The percentage of physical blocks saved on a VDO volume (= [logical blocks used - physical blocks used] / logical blocks used)
VERBOSE OUTPUT¶
The --verbose option displays VDO device statistics in YAML format for the specified VDO devices. The following fields will continue to be reported in future releases. Management tools should not rely upon the order in which any of the statistics are reported.
- version
- The version of these statistics.
- release version
- The release version of the VDO.
- data blocks used
- The number of physical blocks currently in use by a VDO volume to store data.
- overhead blocks used
- The number of physical blocks currently in use by a VDO volume to store VDO metadata.
- logical blocks used
- The number of logical blocks currently mapped.
- physical blocks
- The total number of physical blocks allocated for a VDO volume.
- logical blocks
- The maximum number of logical blocks that can be mapped by a VDO volume.
- 1K-blocks
- The total number of 1K blocks allocated for a VDO volume (= physical volume size * block size / 1024)
- 1K-blocks used
- The total number of 1K blocks used on a VDO volume (= physical blocks used * block size / 1024)
- 1K-blocks available
- The total number of 1K blocks available on a VDO volume (= physical blocks free * block size / 1024)
- used percent
- The percentage of physical blocks used on a VDO volume (= used blocks / allocated blocks * 100)
- saving percent
- The percentage of physical blocks saved on a VDO volume (= [logical blocks used - physical blocks used] / logical blocks used)
- block map cache size
- The size of the block map cache, in bytes.
- write policy
- The write policy (sync, async, or async-unsafe). This is configured via vdo modify --writePolicy=policy.
- block size
- The block size of a VDO volume, in bytes.
- completed recovery count
- The number of times a VDO volume has recovered from an unclean shutdown.
- read-only recovery count
- The number of times a VDO volume has been recovered from read-only mode (via vdo start --forceRebuild).
- operating mode
- Indicates whether a VDO volume is operating normally, is in recovery mode, or is in read-only mode.
- recovery progress (%)
- Indicates online recovery progress, or N/A if the volume is not in recovery mode.
- compressed fragments written
- The number of compressed fragments that have been written since the VDO volume was last restarted.
- compressed blocks written
- The number of physical blocks of compressed data that have been written since the VDO volume was last restarted.
The remaining fields are primarily intended for software support and are subject to change in future releases; management tools should not rely upon them.
- compressed fragments in packer
- The number of compressed fragments being processed that have not yet been written.
- slab count
- The total number of slabs.
- slabs opened
- The total number of slabs from which blocks have ever been allocated.
- slabs reopened
- The number of times slabs have been re-opened since the VDO was started.
- journal disk full count
- The number of times a request could not make a recovery journal entry because the recovery journal was full.
- journal commits requested count
- The number of times the recovery journal requested slab journal commits.
- journal entries batching
- The number of journal entry writes started minus the number of journal entries written.
- journal entries started
- The number of journal entries which have been made in memory.
- journal entries writing
- The number of journal entries in submitted writes minus the number of journal entries committed to storage.
- journal entries written
- The total number of journal entries for which a write has been issued.
- journal entries committed
- The number of journal entries written to storage.
- journal blocks batching
- The number of journal block writes started minus the number of journal blocks written.
- journal blocks started
- The number of journal blocks which have been touched in memory.
- journal blocks writing
- The number of journal blocks written (with metadatata in active memory) minus the number of journal blocks committed.
- journal blocks written
- The total number of journal blocks for which a write has been issued.
- journal blocks committed
- The number of journal blocks written to storage.
- slab journal disk full count
- The number of times an on-disk slab journal was full.
- slab journal flush count
- The number of times an entry was added to a slab journal that was over the flush threshold.
- slab journal blocked count
- The number of times an entry was added to a slab journal that was over the blocking threshold.
- slab journal blocks written
- The number of slab journal block writes issued.
- slab journal tail busy count
- The number of times write requests blocked waiting for a slab journal write.
- slab summary blocks written
- The number of slab summary block writes issued.
- reference blocks written
- The number of reference block writes issued.
- block map dirty pages
- The number of dirty pages in the block map cache.
- block map clean pages
- The number of clean pages in the block map cache.
- block map free pages
- The number of free pages in the block map cache.
- block map failed pages
- The number of block map cache pages that have write errors.
- block map incoming pages
- The number of block map cache pages that are being read into the cache.
- block map outgoing pages
- The number of block map cache pages that are being written.
- block map cache pressure
- The number of times a free page was not available when needed.
- block map read count
- The total number of block map page reads.
- block map write count
- The total number of block map page writes.
- block map failed reads
- The total number of block map read errors.
- block map failed writes
- The total number of block map write errors.
- block map reclaimed
- The total number of block map pages that were reclaimed.
- block map read outgoing
- The total number of block map reads for pages that were being written.
- block map found in cache
- The total number of block map cache hits.
- block map discard required
- The total number of block map requests that required a page to be discarded.
- block map wait for page
- The total number of requests that had to wait for a page.
- block map fetch required
- The total number of requests that required a page fetch.
- block map pages loaded
- The total number of page fetches.
- block map pages saved
- The total number of page saves.
- block map flush count
- The total number of flushes issued by the block map.
- invalid advice PBN count
- The number of times the index returned invalid advice
- no space error count
- The number of write requests which failed due to the VDO volume being out of space.
- read only error count
- The number of write requests which failed due to the VDO volume being in read-only mode.
- instance
- The VDO instance.
- 512 byte emulation
- Indicates whether 512 byte emulation is on or off for the volume.
- current VDO IO requests in progress
- The number of I/O requests the VDO is current processing.
- maximum VDO IO requests in progress
- The maximum number of simultaneous I/O requests the VDO has processed.
- current dedupe queries
- The number of deduplication queries currently in flight.
- maximum dedupe queries
- The maximum number of in-flight deduplication queries.
- dedupe advice valid
- The number of times deduplication advice was correct.
- dedupe advice stale
- The number of times deduplication advice was incorrect.
- dedupe advice timeouts
- The number of times deduplication queries timed out.
- concurrent data matches
- The number of writes with the same data as another in-flight write.
- concurrent hash collisions
- The number of writes whose hash collided with an in-flight write.
- flush out
- The number of flush requests submitted by VDO to the underlying storage.
- write amplification ratio
- The average number of block writes to the underlying storage per block written to the VDO device.
bios in...
bios in partial...
bios out...
bios meta...
bios journal...
bios page cache...
bios out completed...
bios meta completed...
bios journal completed...
bios page cache completed...
bios acknowledged...
bios acknowledged partial...
bios in progress...
- bios in
- The number of block I/O requests received by VDO.
- bios in partial
- The number of partial block I/O requests received by VDO. Applies only to 512-byte emulation mode.
- bios out
- The number of non-metadata block I/O requests submitted by VDO to the storage device.
- bios meta
- The number of metadata block I/O requests submitted by VDO to the storage device.
- bios journal
- The number of recovery journal block I/O requests submitted by VDO to the storage device.
- bios page cache
- The number of block map I/O requests submitted by VDO to the storage device.
- bios out completed
- The number of non-metadata block I/O requests completed by the storage device.
- bios meta completed
- The number of metadata block I/O requests completed by the storage device.
- bios journal completed
- The number of recovery journal block I/O requests completed by the storage device.
- bios page cache completed
- The number of block map I/O requests completed by the storage device.
- bios acknowledged
- The number of block I/O requests acknowledged by VDO.
- bios acknowledged partial
- The number of partial block I/O requests acknowledged by VDO. Applies only to 512-byte emulation mode.
- bios in progress
- The number of bios submitted to the VDO which have not yet been acknowledged.
There are five types of flags:
- read
- The number of non-write bios (bios without the REQ_WRITE flag set)
- write
- The number of write bios (bios with the REQ_WRITE flag set)
- discard
- The number of bios with a REQ_DISCARD flag set
- flush
- The number of flush bios (bios with the REQ_FLUSH flag set)
- fua
- The number of "force unit access" bios (bios with the REQ_FUA flag set)
Note that all bios will be counted as either read or write bios, depending on the REQ_WRITE flag setting, regardless of whether any of the other flags are set.
- KVDO module bytes used
- The current count of bytes allocated by the kernel VDO module.
- KVDO module peak bytes used
- The peak count of bytes allocated by the kernel VDO module, since the module was loaded.
EXAMPLES¶
The following example shows sample output if no options are provided:
Device 1K-blocks Used Available Use% Space Saving% /dev/mapper/my_vdo 1932562432 427698104 1504864328 22% 21%
With the --human-readable option, block counts are converted to conventional units (1 KB = 1024 bytes):
Device Size Used Available Use% Space Saving% /dev/mapper/my_vdo 1.8T 407.9G 1.4T 22% 21%
With the --si option as well, the block counts are reported using SI units (1 KB = 1000 bytes):
Device Size Used Available Use% Space Saving% /dev/mapper/my_vdo 2.0T 438G 1.5T 22% 21%
NOTES¶
The output may be incomplete when the command is run by an unprivileged user.
SEE ALSO¶
2020-02-18 | Red Hat |