1VDOSTATS(8) System Manager's Manual VDOSTATS(8)
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6 vdostats - get configuration and statistics from a running VDO volume
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9 vdostats [--verbose] [--human-readable] [--si] [--all] [--version] [
10 device... ]
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13 The vdostats utility display statistics for each configured (or speci‐
14 fied) VDO device.
15 The default output format is a table with the following columns, simi‐
17 lar to that of the Linux df utility:
18 Device The path to the VDO volume
20 1K-blocks
22 The total number of 1K blocks allocated for a VDO volume (=
23 physical volume size * block size / 1024)
24 Used The total number of 1K blocks used on a VDO volume (= physical
26 blocks used * block size / 1024)
27 Available
29 The total number of 1K blocks available on a VDO volume (= phys‐
30 ical blocks free * block size / 1024)
31 Use% The percentage of physical blocks used on a VDO volume (= used
33 blocks / allocated blocks * 100)
34 Space Saving%
36 The percentage of physical blocks saved on a VDO volume (= [log‐
37 ical blocks used - physical blocks used] / logical blocks used)
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40 The --verbose option displays VDO device statistics in YAML format for
41 the specified VDO devices. The following fields will continue to be
42 reported in future releases. Management tools should not rely upon the
43 order in which any of the statistics are reported.
44 version
46 The version of these statistics.
47 release version
49 The release version of the VDO.
50 data blocks used
52 The number of physical blocks currently in use by a VDO volume
53 to store data.
54 overhead blocks used
56 The number of physical blocks currently in use by a VDO volume
57 to store VDO metadata.
58 logical blocks used
60 The number of logical blocks currently mapped.
61 physical blocks
63 The total number of physical blocks allocated for a VDO volume.
64 logical blocks
66 The maximum number of logical blocks that can be mapped by a VDO
67 volume.
68 1K-blocks
70 The total number of 1K blocks allocated for a VDO volume (=
71 physical volume size * block size / 1024)
72 1K-blocks used
74 The total number of 1K blocks used on a VDO volume (= physical
75 blocks used * block size / 1024)
76 1K-blocks available
78 The total number of 1K blocks available on a VDO volume (= phys‐
79 ical blocks free * block size / 1024)
80 used percent
82 The percentage of physical blocks used on a VDO volume (= used
83 blocks / allocated blocks * 100)
84 saving percent
86 The percentage of physical blocks saved on a VDO volume (= [log‐
87 ical blocks used - physical blocks used] / logical blocks used)
88 block map cache size
90 The size of the block map cache, in bytes.
91 write policy
93 The write policy (sync or async). This is configured via vdo
94 modify --writePolicy=policy.
95 block size
97 The block size of a VDO volume, in bytes.
98 completed recovery count
100 The number of times a VDO volume has recovered from an unclean
101 shutdown.
102 read-only recovery count
104 The number of times a VDO volume has been recovered from read-
105 only mode (via vdo start --forceRebuild).
106 operating mode
108 Indicates whether a VDO volume is operating normally, is in
109 recovery mode, or is in read-only mode.
110 recovery progress (%)
112 Indicates online recovery progress, or N/A if the volume is not
113 in recovery mode.
114 compressed fragments written
116 The number of compressed fragments that have been written since
117 the VDO volume was last restarted.
118 compressed blocks written
120 The number of physical blocks of compressed data that have been
121 written since the VDO volume was last restarted.
122 The remaining fields are primarily intended for software support and
124 are subject to change in future releases; management tools should not
125 rely upon them.
126 compressed fragments in packer
128 The number of compressed fragments being processed that have not
129 yet been written.
130 slab count
132 The total number of slabs.
133 slabs opened
135 The total number of slabs from which blocks have ever been allo‐
136 cated.
137 slabs reopened
139 The number of times slabs have been re-opened since the VDO was
140 started.
141 journal disk full count
143 The number of times a request could not make a recovery journal
144 entry because the recovery journal was full.
145 journal commits requested count
147 The number of times the recovery journal requested slab journal
148 commits.
149 journal entries batching
151 The number of journal entry writes started minus the number of
152 journal entries written.
153 journal entries started
155 The number of journal entries which have been made in memory.
156 journal entries writing
158 The number of journal entries in submitted writes minus the num‐
159 ber of journal entries committed to storage.
160 journal entries written
162 The total number of journal entries for which a write has been
163 issued.
164 journal entries committed
166 The number of journal entries written to storage.
167 journal blocks batching
169 The number of journal block writes started minus the number of
170 journal blocks written.
171 journal blocks started
173 The number of journal blocks which have been touched in memory.
174 journal blocks writing
176 The number of journal blocks written (with metadatata in active
177 memory) minus the number of journal blocks committed.
178 journal blocks written
180 The total number of journal blocks for which a write has been
181 issued.
182 journal blocks committed
184 The number of journal blocks written to storage.
185 slab journal disk full count
187 The number of times an on-disk slab journal was full.
188 slab journal flush count
190 The number of times an entry was added to a slab journal that
191 was over the flush threshold.
192 slab journal blocked count
194 The number of times an entry was added to a slab journal that
195 was over the blocking threshold.
196 slab journal blocks written
198 The number of slab journal block writes issued.
199 slab journal tail busy count
201 The number of times write requests blocked waiting for a slab
202 journal write.
203 slab summary blocks written
205 The number of slab summary block writes issued.
206 reference blocks written
208 The number of reference block writes issued.
209 block map dirty pages
211 The number of dirty pages in the block map cache.
212 block map clean pages
214 The number of clean pages in the block map cache.
215 block map free pages
217 The number of free pages in the block map cache.
218 block map failed pages
220 The number of block map cache pages that have write errors.
221 block map incoming pages
223 The number of block map cache pages that are being read into the
224 cache.
225 block map outgoing pages
227 The number of block map cache pages that are being written.
228 block map cache pressure
230 The number of times a free page was not available when needed.
231 block map read count
233 The total number of block map page reads.
234 block map write count
236 The total number of block map page writes.
237 block map failed reads
239 The total number of block map read errors.
240 block map failed writes
242 The total number of block map write errors.
243 block map reclaimed
245 The total number of block map pages that were reclaimed.
246 block map read outgoing
248 The total number of block map reads for pages that were being
249 written.
250 block map found in cache
252 The total number of block map cache hits.
253 block map discard required
255 The total number of block map requests that required a page to
256 be discarded.
257 block map wait for page
259 The total number of requests that had to wait for a page.
260 block map fetch required
262 The total number of requests that required a page fetch.
263 block map pages loaded
265 The total number of page fetches.
266 block map pages saved
268 The total number of page saves.
269 block map flush count
271 The total number of flushes issued by the block map.
272 invalid advice PBN count
274 The number of times the index returned invalid advice
275 no space error count
277 The number of write requests which failed due to the VDO volume
278 being out of space.
279 read only error count
281 The number of write requests which failed due to the VDO volume
282 being in read-only mode.
283 instance
285 The VDO instance.
286 512 byte emulation
288 Indicates whether 512 byte emulation is on or off for the vol‐
289 ume.
290 current VDO IO requests in progress
292 The number of I/O requests the VDO is current processing.
293 maximum VDO IO requests in progress
295 The maximum number of simultaneous I/O requests the VDO has pro‐
296 cessed.
297 current dedupe queries
299 The number of deduplication queries currently in flight.
300 maximum dedupe queries
302 The maximum number of in-flight deduplication queries.
303 dedupe advice valid
305 The number of times deduplication advice was correct.
306 dedupe advice stale
308 The number of times deduplication advice was incorrect.
309 dedupe advice timeouts
311 The number of times deduplication queries timed out.
312 concurrent data matches
314 The number of writes with the same data as another in-flight
315 write.
316 concurrent hash collisions
318 The number of writes whose hash collided with an in-flight
319 write.
320 flush out
322 The number of flush requests submitted by VDO to the underlying
323 storage.
324 write amplification ratio
326 The average number of block writes to the underlying storage per
327 block written to the VDO device.
328 bios in...
330 bios in partial...
331 bios out...
332 bios meta...
333 bios journal...
334 bios page cache...
335 bios out completed...
336 bios meta completed...
337 bios journal completed...
338 bios page cache completed...
339 bios acknowledged...
340 bios acknowledged partial...
341 bios in progress...
342 These statistics count the number of bios in each category with
343 a given flag. The categories are:
344 bios in
346 The number of block I/O requests received by VDO.
347 bios in partial
349 The number of partial block I/O requests received by VDO.
350 Applies only to 512-byte emulation mode.
351 bios out
353 The number of non-metadata block I/O requests submitted
354 by VDO to the storage device.
355 bios meta
357 The number of metadata block I/O requests submitted by
358 VDO to the storage device.
359 bios journal
361 The number of recovery journal block I/O requests submit‐
362 ted by VDO to the storage device.
363 bios page cache
365 The number of block map I/O requests submitted by VDO to
366 the storage device.
367 bios out completed
369 The number of non-metadata block I/O requests completed
370 by the storage device.
371 bios meta completed
373 The number of metadata block I/O requests completed by
374 the storage device.
375 bios journal completed
377 The number of recovery journal block I/O requests com‐
378 pleted by the storage device.
379 bios page cache completed
381 The number of block map I/O requests completed by the
382 storage device.
383 bios acknowledged
385 The number of block I/O requests acknowledged by VDO.
386 bios acknowledged partial
388 The number of partial block I/O requests acknowledged by
389 VDO. Applies only to 512-byte emulation mode.
390 bios in progress
392 The number of bios submitted to the VDO which have not
393 yet been acknowledged.
394 There are five types of flags:
396 read The number of non-write bios (bios without the REQ_WRITE
398 flag set)
399 write The number of write bios (bios with the REQ_WRITE flag
401 set)
402 discard
404 The number of bios with a REQ_DISCARD flag set
405 flush The number of flush bios (bios with the REQ_FLUSH flag
407 set)
408 fua The number of "force unit access" bios (bios with the
410 REQ_FUA flag set)
411 Note that all bios will be counted as either read or write bios,
413 depending on the REQ_WRITE flag setting, regardless of whether
414 any of the other flags are set.
415 KVDO module bios used
417 The current number of kernel "struct bio" structures allocated
418 by the kernel VDO module.
419 KVDO module peak bio count
421 The peak number of kernel "struct bio" structures allocated by
422 the kernel VDO module, since the module was loaded.
423 KVDO module bytes used
425 The current count of bytes allocated by the kernel VDO module.
426 KVDO module peak bytes used
428 The peak count of bytes allocated by the kernel VDO module,
429 since the module was loaded.
430
432 --verbose
433 Displays the utilization and block I/O (bios) statistics for the
434 selected VDO devices.
435 --human-readable
437 Displays block values in readable form (Base 2: 1 KB = 2^10
438 bytes = 1024 bytes).
439 --si Modifies the output of the --human-readable option to use SI
441 units (Base 10: 1 KB = 10^3 bytes = 1000 bytes). If the
442 --human-readable option is not supplied, this option has no
443 effect.
444 --all This option is only for backwards compatibility. It is now
446 equivalent to --verbose.
447 --version
449 Displays the vdostats version.
450 device...
452 Specifies one or more specific volumes to report on. If this
453 argument is omitted, vdostats will report on all devices.
454
456 The following example shows sample output if no options are provided:
457 Device 1K-blocks Used Available Use% Space Saving%
459 /dev/mapper/my_vdo 1932562432 427698104 1504864328 22% 21%
460 With the --human-readable option, block counts are converted to conven‐
462 tional units (1 KB = 1024 bytes):
463 Device Size Used Available Use% Space Saving%
465 /dev/mapper/my_vdo 1.8T 407.9G 1.4T 22% 21%
466 With the --si option as well, the block counts are reported using SI
468 units (1 KB = 1000 bytes):
469 Device Size Used Available Use% Space Saving%
471 /dev/mapper/my_vdo 2.0T 438G 1.5T 22% 21%
472
474 The output may be incomplete when the command is run by an unprivileged
475 user.
476
478 vdo(8).
479Red Hat 2018-07-18 VDOSTATS(8)