]>
Commit | Line | Data |
---|---|---|
a08ee875 LG |
1 | /* |
2 | * CDDL HEADER START | |
3 | * | |
4 | * The contents of this file are subject to the terms of the | |
5 | * Common Development and Distribution License (the "License"). | |
6 | * You may not use this file except in compliance with the License. | |
7 | * | |
8 | * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE | |
9 | * or http://www.opensolaris.org/os/licensing. | |
10 | * See the License for the specific language governing permissions | |
11 | * and limitations under the License. | |
12 | * | |
13 | * When distributing Covered Code, include this CDDL HEADER in each | |
14 | * file and include the License file at usr/src/OPENSOLARIS.LICENSE. | |
15 | * If applicable, add the following below this CDDL HEADER, with the | |
16 | * fields enclosed by brackets "[]" replaced with your own identifying | |
17 | * information: Portions Copyright [yyyy] [name of copyright owner] | |
18 | * | |
19 | * CDDL HEADER END | |
20 | */ | |
21 | ||
22 | #include <sys/zfs_context.h> | |
23 | #include <sys/spa_impl.h> | |
cae5b340 | 24 | #include <sys/vdev_impl.h> |
a07c8b41 MZ |
25 | #include <sys/spa.h> |
26 | #include <zfs_comutil.h> | |
a08ee875 LG |
27 | |
28 | /* | |
29 | * Keeps stats on last N reads per spa_t, disabled by default. | |
30 | */ | |
31 | int zfs_read_history = 0; | |
32 | ||
33 | /* | |
34 | * Include cache hits in history, disabled by default. | |
35 | */ | |
36 | int zfs_read_history_hits = 0; | |
37 | ||
38 | /* | |
39 | * Keeps stats on the last N txgs, disabled by default. | |
40 | */ | |
41 | int zfs_txg_history = 0; | |
42 | ||
cae5b340 AX |
43 | /* |
44 | * Keeps stats on the last N MMP updates, disabled by default. | |
45 | */ | |
46 | int zfs_multihost_history = 0; | |
47 | ||
a08ee875 LG |
48 | /* |
49 | * ========================================================================== | |
50 | * SPA Read History Routines | |
51 | * ========================================================================== | |
52 | */ | |
53 | ||
54 | /* | |
55 | * Read statistics - Information exported regarding each arc_read call | |
56 | */ | |
57 | typedef struct spa_read_history { | |
58 | uint64_t uid; /* unique identifier */ | |
59 | hrtime_t start; /* time read completed */ | |
60 | uint64_t objset; /* read from this objset */ | |
61 | uint64_t object; /* read of this object number */ | |
62 | uint64_t level; /* block's indirection level */ | |
63 | uint64_t blkid; /* read of this block id */ | |
64 | char origin[24]; /* read originated from here */ | |
65 | uint32_t aflags; /* ARC flags (cached, prefetch, etc.) */ | |
66 | pid_t pid; /* PID of task doing read */ | |
67 | char comm[16]; /* process name of task doing read */ | |
68 | list_node_t srh_link; | |
69 | } spa_read_history_t; | |
70 | ||
71 | static int | |
72 | spa_read_history_headers(char *buf, size_t size) | |
73 | { | |
ea04106b | 74 | (void) snprintf(buf, size, "%-8s %-16s %-8s %-8s %-8s %-8s %-8s " |
a08ee875 LG |
75 | "%-24s %-8s %-16s\n", "UID", "start", "objset", "object", |
76 | "level", "blkid", "aflags", "origin", "pid", "process"); | |
a08ee875 LG |
77 | |
78 | return (0); | |
79 | } | |
80 | ||
81 | static int | |
82 | spa_read_history_data(char *buf, size_t size, void *data) | |
83 | { | |
84 | spa_read_history_t *srh = (spa_read_history_t *)data; | |
85 | ||
ea04106b | 86 | (void) snprintf(buf, size, "%-8llu %-16llu 0x%-6llx " |
a08ee875 LG |
87 | "%-8lli %-8lli %-8lli 0x%-6x %-24s %-8i %-16s\n", |
88 | (u_longlong_t)srh->uid, srh->start, | |
89 | (longlong_t)srh->objset, (longlong_t)srh->object, | |
90 | (longlong_t)srh->level, (longlong_t)srh->blkid, | |
91 | srh->aflags, srh->origin, srh->pid, srh->comm); | |
a08ee875 LG |
92 | |
93 | return (0); | |
94 | } | |
95 | ||
96 | /* | |
97 | * Calculate the address for the next spa_stats_history_t entry. The | |
98 | * ssh->lock will be held until ksp->ks_ndata entries are processed. | |
99 | */ | |
100 | static void * | |
101 | spa_read_history_addr(kstat_t *ksp, loff_t n) | |
102 | { | |
103 | spa_t *spa = ksp->ks_private; | |
104 | spa_stats_history_t *ssh = &spa->spa_stats.read_history; | |
105 | ||
106 | ASSERT(MUTEX_HELD(&ssh->lock)); | |
107 | ||
108 | if (n == 0) | |
109 | ssh->private = list_tail(&ssh->list); | |
110 | else if (ssh->private) | |
111 | ssh->private = list_prev(&ssh->list, ssh->private); | |
112 | ||
113 | return (ssh->private); | |
114 | } | |
115 | ||
116 | /* | |
cae5b340 | 117 | * When the kstat is written discard all spa_read_history_t entries. The |
a08ee875 LG |
118 | * ssh->lock will be held until ksp->ks_ndata entries are processed. |
119 | */ | |
120 | static int | |
121 | spa_read_history_update(kstat_t *ksp, int rw) | |
122 | { | |
123 | spa_t *spa = ksp->ks_private; | |
124 | spa_stats_history_t *ssh = &spa->spa_stats.read_history; | |
125 | ||
126 | if (rw == KSTAT_WRITE) { | |
127 | spa_read_history_t *srh; | |
128 | ||
129 | while ((srh = list_remove_head(&ssh->list))) { | |
130 | ssh->size--; | |
131 | kmem_free(srh, sizeof (spa_read_history_t)); | |
132 | } | |
133 | ||
134 | ASSERT3U(ssh->size, ==, 0); | |
135 | } | |
136 | ||
137 | ksp->ks_ndata = ssh->size; | |
138 | ksp->ks_data_size = ssh->size * sizeof (spa_read_history_t); | |
139 | ||
140 | return (0); | |
141 | } | |
142 | ||
143 | static void | |
144 | spa_read_history_init(spa_t *spa) | |
145 | { | |
146 | spa_stats_history_t *ssh = &spa->spa_stats.read_history; | |
147 | char name[KSTAT_STRLEN]; | |
148 | kstat_t *ksp; | |
149 | ||
150 | mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL); | |
151 | list_create(&ssh->list, sizeof (spa_read_history_t), | |
152 | offsetof(spa_read_history_t, srh_link)); | |
153 | ||
154 | ssh->count = 0; | |
155 | ssh->size = 0; | |
156 | ssh->private = NULL; | |
157 | ||
158 | (void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa)); | |
a08ee875 LG |
159 | |
160 | ksp = kstat_create(name, 0, "reads", "misc", | |
161 | KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL); | |
162 | ssh->kstat = ksp; | |
163 | ||
164 | if (ksp) { | |
165 | ksp->ks_lock = &ssh->lock; | |
166 | ksp->ks_data = NULL; | |
167 | ksp->ks_private = spa; | |
168 | ksp->ks_update = spa_read_history_update; | |
169 | kstat_set_raw_ops(ksp, spa_read_history_headers, | |
170 | spa_read_history_data, spa_read_history_addr); | |
171 | kstat_install(ksp); | |
172 | } | |
173 | } | |
174 | ||
175 | static void | |
176 | spa_read_history_destroy(spa_t *spa) | |
177 | { | |
178 | spa_stats_history_t *ssh = &spa->spa_stats.read_history; | |
179 | spa_read_history_t *srh; | |
180 | kstat_t *ksp; | |
181 | ||
182 | ksp = ssh->kstat; | |
183 | if (ksp) | |
184 | kstat_delete(ksp); | |
185 | ||
186 | mutex_enter(&ssh->lock); | |
187 | while ((srh = list_remove_head(&ssh->list))) { | |
188 | ssh->size--; | |
189 | kmem_free(srh, sizeof (spa_read_history_t)); | |
190 | } | |
191 | ||
192 | ASSERT3U(ssh->size, ==, 0); | |
193 | list_destroy(&ssh->list); | |
194 | mutex_exit(&ssh->lock); | |
195 | ||
196 | mutex_destroy(&ssh->lock); | |
197 | } | |
198 | ||
199 | void | |
ea04106b | 200 | spa_read_history_add(spa_t *spa, const zbookmark_phys_t *zb, uint32_t aflags) |
a08ee875 LG |
201 | { |
202 | spa_stats_history_t *ssh = &spa->spa_stats.read_history; | |
203 | spa_read_history_t *srh, *rm; | |
204 | ||
205 | ASSERT3P(spa, !=, NULL); | |
206 | ASSERT3P(zb, !=, NULL); | |
207 | ||
208 | if (zfs_read_history == 0 && ssh->size == 0) | |
209 | return; | |
210 | ||
e10b0808 | 211 | if (zfs_read_history_hits == 0 && (aflags & ARC_FLAG_CACHED)) |
a08ee875 LG |
212 | return; |
213 | ||
ea04106b | 214 | srh = kmem_zalloc(sizeof (spa_read_history_t), KM_SLEEP); |
a08ee875 LG |
215 | strlcpy(srh->comm, getcomm(), sizeof (srh->comm)); |
216 | srh->start = gethrtime(); | |
217 | srh->objset = zb->zb_objset; | |
218 | srh->object = zb->zb_object; | |
219 | srh->level = zb->zb_level; | |
220 | srh->blkid = zb->zb_blkid; | |
221 | srh->aflags = aflags; | |
222 | srh->pid = getpid(); | |
223 | ||
224 | mutex_enter(&ssh->lock); | |
225 | ||
226 | srh->uid = ssh->count++; | |
227 | list_insert_head(&ssh->list, srh); | |
228 | ssh->size++; | |
229 | ||
230 | while (ssh->size > zfs_read_history) { | |
231 | ssh->size--; | |
232 | rm = list_remove_tail(&ssh->list); | |
233 | kmem_free(rm, sizeof (spa_read_history_t)); | |
234 | } | |
235 | ||
236 | mutex_exit(&ssh->lock); | |
237 | } | |
238 | ||
239 | /* | |
240 | * ========================================================================== | |
241 | * SPA TXG History Routines | |
242 | * ========================================================================== | |
243 | */ | |
244 | ||
245 | /* | |
246 | * Txg statistics - Information exported regarding each txg sync | |
247 | */ | |
248 | ||
249 | typedef struct spa_txg_history { | |
250 | uint64_t txg; /* txg id */ | |
251 | txg_state_t state; /* active txg state */ | |
252 | uint64_t nread; /* number of bytes read */ | |
253 | uint64_t nwritten; /* number of bytes written */ | |
254 | uint64_t reads; /* number of read operations */ | |
255 | uint64_t writes; /* number of write operations */ | |
ea04106b | 256 | uint64_t ndirty; /* number of dirty bytes */ |
a08ee875 LG |
257 | hrtime_t times[TXG_STATE_COMMITTED]; /* completion times */ |
258 | list_node_t sth_link; | |
259 | } spa_txg_history_t; | |
260 | ||
261 | static int | |
262 | spa_txg_history_headers(char *buf, size_t size) | |
263 | { | |
ea04106b | 264 | (void) snprintf(buf, size, "%-8s %-16s %-5s %-12s %-12s %-12s " |
a08ee875 | 265 | "%-8s %-8s %-12s %-12s %-12s %-12s\n", "txg", "birth", "state", |
ea04106b | 266 | "ndirty", "nread", "nwritten", "reads", "writes", |
a08ee875 | 267 | "otime", "qtime", "wtime", "stime"); |
a08ee875 LG |
268 | |
269 | return (0); | |
270 | } | |
271 | ||
272 | static int | |
273 | spa_txg_history_data(char *buf, size_t size, void *data) | |
274 | { | |
275 | spa_txg_history_t *sth = (spa_txg_history_t *)data; | |
276 | uint64_t open = 0, quiesce = 0, wait = 0, sync = 0; | |
277 | char state; | |
278 | ||
279 | switch (sth->state) { | |
280 | case TXG_STATE_BIRTH: state = 'B'; break; | |
281 | case TXG_STATE_OPEN: state = 'O'; break; | |
282 | case TXG_STATE_QUIESCED: state = 'Q'; break; | |
283 | case TXG_STATE_WAIT_FOR_SYNC: state = 'W'; break; | |
284 | case TXG_STATE_SYNCED: state = 'S'; break; | |
285 | case TXG_STATE_COMMITTED: state = 'C'; break; | |
286 | default: state = '?'; break; | |
287 | } | |
288 | ||
289 | if (sth->times[TXG_STATE_OPEN]) | |
290 | open = sth->times[TXG_STATE_OPEN] - | |
291 | sth->times[TXG_STATE_BIRTH]; | |
292 | ||
293 | if (sth->times[TXG_STATE_QUIESCED]) | |
294 | quiesce = sth->times[TXG_STATE_QUIESCED] - | |
295 | sth->times[TXG_STATE_OPEN]; | |
296 | ||
297 | if (sth->times[TXG_STATE_WAIT_FOR_SYNC]) | |
298 | wait = sth->times[TXG_STATE_WAIT_FOR_SYNC] - | |
299 | sth->times[TXG_STATE_QUIESCED]; | |
300 | ||
301 | if (sth->times[TXG_STATE_SYNCED]) | |
302 | sync = sth->times[TXG_STATE_SYNCED] - | |
303 | sth->times[TXG_STATE_WAIT_FOR_SYNC]; | |
304 | ||
ea04106b | 305 | (void) snprintf(buf, size, "%-8llu %-16llu %-5c %-12llu " |
a08ee875 LG |
306 | "%-12llu %-12llu %-8llu %-8llu %-12llu %-12llu %-12llu %-12llu\n", |
307 | (longlong_t)sth->txg, sth->times[TXG_STATE_BIRTH], state, | |
ea04106b | 308 | (u_longlong_t)sth->ndirty, |
a08ee875 LG |
309 | (u_longlong_t)sth->nread, (u_longlong_t)sth->nwritten, |
310 | (u_longlong_t)sth->reads, (u_longlong_t)sth->writes, | |
311 | (u_longlong_t)open, (u_longlong_t)quiesce, (u_longlong_t)wait, | |
312 | (u_longlong_t)sync); | |
a08ee875 LG |
313 | |
314 | return (0); | |
315 | } | |
316 | ||
317 | /* | |
318 | * Calculate the address for the next spa_stats_history_t entry. The | |
319 | * ssh->lock will be held until ksp->ks_ndata entries are processed. | |
320 | */ | |
321 | static void * | |
322 | spa_txg_history_addr(kstat_t *ksp, loff_t n) | |
323 | { | |
324 | spa_t *spa = ksp->ks_private; | |
325 | spa_stats_history_t *ssh = &spa->spa_stats.txg_history; | |
326 | ||
327 | ASSERT(MUTEX_HELD(&ssh->lock)); | |
328 | ||
329 | if (n == 0) | |
330 | ssh->private = list_tail(&ssh->list); | |
331 | else if (ssh->private) | |
332 | ssh->private = list_prev(&ssh->list, ssh->private); | |
333 | ||
334 | return (ssh->private); | |
335 | } | |
336 | ||
337 | /* | |
cae5b340 | 338 | * When the kstat is written discard all spa_txg_history_t entries. The |
a08ee875 LG |
339 | * ssh->lock will be held until ksp->ks_ndata entries are processed. |
340 | */ | |
341 | static int | |
342 | spa_txg_history_update(kstat_t *ksp, int rw) | |
343 | { | |
344 | spa_t *spa = ksp->ks_private; | |
345 | spa_stats_history_t *ssh = &spa->spa_stats.txg_history; | |
346 | ||
347 | ASSERT(MUTEX_HELD(&ssh->lock)); | |
348 | ||
349 | if (rw == KSTAT_WRITE) { | |
350 | spa_txg_history_t *sth; | |
351 | ||
352 | while ((sth = list_remove_head(&ssh->list))) { | |
353 | ssh->size--; | |
354 | kmem_free(sth, sizeof (spa_txg_history_t)); | |
355 | } | |
356 | ||
357 | ASSERT3U(ssh->size, ==, 0); | |
358 | } | |
359 | ||
360 | ksp->ks_ndata = ssh->size; | |
361 | ksp->ks_data_size = ssh->size * sizeof (spa_txg_history_t); | |
362 | ||
363 | return (0); | |
364 | } | |
365 | ||
366 | static void | |
367 | spa_txg_history_init(spa_t *spa) | |
368 | { | |
369 | spa_stats_history_t *ssh = &spa->spa_stats.txg_history; | |
370 | char name[KSTAT_STRLEN]; | |
371 | kstat_t *ksp; | |
372 | ||
373 | mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL); | |
374 | list_create(&ssh->list, sizeof (spa_txg_history_t), | |
375 | offsetof(spa_txg_history_t, sth_link)); | |
376 | ||
377 | ssh->count = 0; | |
378 | ssh->size = 0; | |
379 | ssh->private = NULL; | |
380 | ||
381 | (void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa)); | |
a08ee875 LG |
382 | |
383 | ksp = kstat_create(name, 0, "txgs", "misc", | |
384 | KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL); | |
385 | ssh->kstat = ksp; | |
386 | ||
387 | if (ksp) { | |
388 | ksp->ks_lock = &ssh->lock; | |
389 | ksp->ks_data = NULL; | |
390 | ksp->ks_private = spa; | |
391 | ksp->ks_update = spa_txg_history_update; | |
392 | kstat_set_raw_ops(ksp, spa_txg_history_headers, | |
393 | spa_txg_history_data, spa_txg_history_addr); | |
394 | kstat_install(ksp); | |
395 | } | |
396 | } | |
397 | ||
398 | static void | |
399 | spa_txg_history_destroy(spa_t *spa) | |
400 | { | |
401 | spa_stats_history_t *ssh = &spa->spa_stats.txg_history; | |
402 | spa_txg_history_t *sth; | |
403 | kstat_t *ksp; | |
404 | ||
405 | ksp = ssh->kstat; | |
406 | if (ksp) | |
407 | kstat_delete(ksp); | |
408 | ||
409 | mutex_enter(&ssh->lock); | |
410 | while ((sth = list_remove_head(&ssh->list))) { | |
411 | ssh->size--; | |
412 | kmem_free(sth, sizeof (spa_txg_history_t)); | |
413 | } | |
414 | ||
415 | ASSERT3U(ssh->size, ==, 0); | |
416 | list_destroy(&ssh->list); | |
417 | mutex_exit(&ssh->lock); | |
418 | ||
419 | mutex_destroy(&ssh->lock); | |
420 | } | |
421 | ||
422 | /* | |
423 | * Add a new txg to historical record. | |
424 | */ | |
425 | void | |
426 | spa_txg_history_add(spa_t *spa, uint64_t txg, hrtime_t birth_time) | |
427 | { | |
428 | spa_stats_history_t *ssh = &spa->spa_stats.txg_history; | |
429 | spa_txg_history_t *sth, *rm; | |
430 | ||
431 | if (zfs_txg_history == 0 && ssh->size == 0) | |
432 | return; | |
433 | ||
ea04106b | 434 | sth = kmem_zalloc(sizeof (spa_txg_history_t), KM_SLEEP); |
a08ee875 LG |
435 | sth->txg = txg; |
436 | sth->state = TXG_STATE_OPEN; | |
437 | sth->times[TXG_STATE_BIRTH] = birth_time; | |
438 | ||
439 | mutex_enter(&ssh->lock); | |
440 | ||
441 | list_insert_head(&ssh->list, sth); | |
442 | ssh->size++; | |
443 | ||
444 | while (ssh->size > zfs_txg_history) { | |
445 | ssh->size--; | |
446 | rm = list_remove_tail(&ssh->list); | |
447 | kmem_free(rm, sizeof (spa_txg_history_t)); | |
448 | } | |
449 | ||
450 | mutex_exit(&ssh->lock); | |
451 | } | |
452 | ||
453 | /* | |
454 | * Set txg state completion time and increment current state. | |
455 | */ | |
456 | int | |
457 | spa_txg_history_set(spa_t *spa, uint64_t txg, txg_state_t completed_state, | |
458 | hrtime_t completed_time) | |
459 | { | |
460 | spa_stats_history_t *ssh = &spa->spa_stats.txg_history; | |
461 | spa_txg_history_t *sth; | |
462 | int error = ENOENT; | |
463 | ||
464 | if (zfs_txg_history == 0) | |
465 | return (0); | |
466 | ||
467 | mutex_enter(&ssh->lock); | |
468 | for (sth = list_head(&ssh->list); sth != NULL; | |
469 | sth = list_next(&ssh->list, sth)) { | |
470 | if (sth->txg == txg) { | |
471 | sth->times[completed_state] = completed_time; | |
472 | sth->state++; | |
473 | error = 0; | |
474 | break; | |
475 | } | |
476 | } | |
477 | mutex_exit(&ssh->lock); | |
478 | ||
479 | return (error); | |
480 | } | |
481 | ||
482 | /* | |
483 | * Set txg IO stats. | |
484 | */ | |
cae5b340 | 485 | static int |
a08ee875 | 486 | spa_txg_history_set_io(spa_t *spa, uint64_t txg, uint64_t nread, |
ea04106b | 487 | uint64_t nwritten, uint64_t reads, uint64_t writes, uint64_t ndirty) |
a08ee875 LG |
488 | { |
489 | spa_stats_history_t *ssh = &spa->spa_stats.txg_history; | |
490 | spa_txg_history_t *sth; | |
491 | int error = ENOENT; | |
492 | ||
493 | if (zfs_txg_history == 0) | |
494 | return (0); | |
495 | ||
496 | mutex_enter(&ssh->lock); | |
497 | for (sth = list_head(&ssh->list); sth != NULL; | |
498 | sth = list_next(&ssh->list, sth)) { | |
499 | if (sth->txg == txg) { | |
500 | sth->nread = nread; | |
501 | sth->nwritten = nwritten; | |
502 | sth->reads = reads; | |
503 | sth->writes = writes; | |
ea04106b | 504 | sth->ndirty = ndirty; |
a08ee875 LG |
505 | error = 0; |
506 | break; | |
507 | } | |
508 | } | |
509 | mutex_exit(&ssh->lock); | |
510 | ||
511 | return (error); | |
512 | } | |
513 | ||
cae5b340 AX |
514 | txg_stat_t * |
515 | spa_txg_history_init_io(spa_t *spa, uint64_t txg, dsl_pool_t *dp) | |
516 | { | |
517 | txg_stat_t *ts; | |
518 | ||
519 | if (zfs_txg_history == 0) | |
520 | return (NULL); | |
521 | ||
522 | ts = kmem_alloc(sizeof (txg_stat_t), KM_SLEEP); | |
523 | ||
524 | spa_config_enter(spa, SCL_ALL, FTAG, RW_READER); | |
525 | vdev_get_stats(spa->spa_root_vdev, &ts->vs1); | |
526 | spa_config_exit(spa, SCL_ALL, FTAG); | |
527 | ||
528 | ts->txg = txg; | |
529 | ts->ndirty = dp->dp_dirty_pertxg[txg & TXG_MASK]; | |
530 | ||
531 | spa_txg_history_set(spa, txg, TXG_STATE_WAIT_FOR_SYNC, gethrtime()); | |
532 | ||
533 | return (ts); | |
534 | } | |
535 | ||
536 | void | |
537 | spa_txg_history_fini_io(spa_t *spa, txg_stat_t *ts) | |
538 | { | |
539 | if (ts == NULL) | |
540 | return; | |
541 | ||
542 | if (zfs_txg_history == 0) { | |
543 | kmem_free(ts, sizeof (txg_stat_t)); | |
544 | return; | |
545 | } | |
546 | ||
547 | spa_config_enter(spa, SCL_ALL, FTAG, RW_READER); | |
548 | vdev_get_stats(spa->spa_root_vdev, &ts->vs2); | |
549 | spa_config_exit(spa, SCL_ALL, FTAG); | |
550 | ||
551 | spa_txg_history_set(spa, ts->txg, TXG_STATE_SYNCED, gethrtime()); | |
552 | spa_txg_history_set_io(spa, ts->txg, | |
553 | ts->vs2.vs_bytes[ZIO_TYPE_READ] - ts->vs1.vs_bytes[ZIO_TYPE_READ], | |
554 | ts->vs2.vs_bytes[ZIO_TYPE_WRITE] - ts->vs1.vs_bytes[ZIO_TYPE_WRITE], | |
555 | ts->vs2.vs_ops[ZIO_TYPE_READ] - ts->vs1.vs_ops[ZIO_TYPE_READ], | |
556 | ts->vs2.vs_ops[ZIO_TYPE_WRITE] - ts->vs1.vs_ops[ZIO_TYPE_WRITE], | |
557 | ts->ndirty); | |
558 | ||
559 | kmem_free(ts, sizeof (txg_stat_t)); | |
560 | } | |
561 | ||
a08ee875 LG |
562 | /* |
563 | * ========================================================================== | |
564 | * SPA TX Assign Histogram Routines | |
565 | * ========================================================================== | |
566 | */ | |
567 | ||
568 | /* | |
569 | * Tx statistics - Information exported regarding dmu_tx_assign time. | |
570 | */ | |
571 | ||
572 | /* | |
573 | * When the kstat is written zero all buckets. When the kstat is read | |
574 | * count the number of trailing buckets set to zero and update ks_ndata | |
575 | * such that they are not output. | |
576 | */ | |
577 | static int | |
578 | spa_tx_assign_update(kstat_t *ksp, int rw) | |
579 | { | |
580 | spa_t *spa = ksp->ks_private; | |
581 | spa_stats_history_t *ssh = &spa->spa_stats.tx_assign_histogram; | |
582 | int i; | |
583 | ||
584 | if (rw == KSTAT_WRITE) { | |
585 | for (i = 0; i < ssh->count; i++) | |
586 | ((kstat_named_t *)ssh->private)[i].value.ui64 = 0; | |
587 | } | |
588 | ||
589 | for (i = ssh->count; i > 0; i--) | |
590 | if (((kstat_named_t *)ssh->private)[i-1].value.ui64 != 0) | |
591 | break; | |
592 | ||
593 | ksp->ks_ndata = i; | |
594 | ksp->ks_data_size = i * sizeof (kstat_named_t); | |
595 | ||
596 | return (0); | |
597 | } | |
598 | ||
599 | static void | |
600 | spa_tx_assign_init(spa_t *spa) | |
601 | { | |
602 | spa_stats_history_t *ssh = &spa->spa_stats.tx_assign_histogram; | |
603 | char name[KSTAT_STRLEN]; | |
604 | kstat_named_t *ks; | |
605 | kstat_t *ksp; | |
606 | int i; | |
607 | ||
608 | mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL); | |
609 | ||
610 | ssh->count = 42; /* power of two buckets for 1ns to 2,199s */ | |
611 | ssh->size = ssh->count * sizeof (kstat_named_t); | |
612 | ssh->private = kmem_alloc(ssh->size, KM_SLEEP); | |
613 | ||
614 | (void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa)); | |
a08ee875 LG |
615 | |
616 | for (i = 0; i < ssh->count; i++) { | |
617 | ks = &((kstat_named_t *)ssh->private)[i]; | |
618 | ks->data_type = KSTAT_DATA_UINT64; | |
619 | ks->value.ui64 = 0; | |
620 | (void) snprintf(ks->name, KSTAT_STRLEN, "%llu ns", | |
621 | (u_longlong_t)1 << i); | |
622 | } | |
623 | ||
624 | ksp = kstat_create(name, 0, "dmu_tx_assign", "misc", | |
625 | KSTAT_TYPE_NAMED, 0, KSTAT_FLAG_VIRTUAL); | |
626 | ssh->kstat = ksp; | |
627 | ||
628 | if (ksp) { | |
629 | ksp->ks_lock = &ssh->lock; | |
630 | ksp->ks_data = ssh->private; | |
631 | ksp->ks_ndata = ssh->count; | |
632 | ksp->ks_data_size = ssh->size; | |
633 | ksp->ks_private = spa; | |
634 | ksp->ks_update = spa_tx_assign_update; | |
635 | kstat_install(ksp); | |
636 | } | |
637 | } | |
638 | ||
639 | static void | |
640 | spa_tx_assign_destroy(spa_t *spa) | |
641 | { | |
642 | spa_stats_history_t *ssh = &spa->spa_stats.tx_assign_histogram; | |
643 | kstat_t *ksp; | |
644 | ||
645 | ksp = ssh->kstat; | |
646 | if (ksp) | |
647 | kstat_delete(ksp); | |
648 | ||
649 | kmem_free(ssh->private, ssh->size); | |
650 | mutex_destroy(&ssh->lock); | |
651 | } | |
652 | ||
653 | void | |
654 | spa_tx_assign_add_nsecs(spa_t *spa, uint64_t nsecs) | |
655 | { | |
656 | spa_stats_history_t *ssh = &spa->spa_stats.tx_assign_histogram; | |
657 | uint64_t idx = 0; | |
658 | ||
cae5b340 | 659 | while (((1ULL << idx) < nsecs) && (idx < ssh->size - 1)) |
a08ee875 LG |
660 | idx++; |
661 | ||
662 | atomic_inc_64(&((kstat_named_t *)ssh->private)[idx].value.ui64); | |
663 | } | |
664 | ||
665 | /* | |
666 | * ========================================================================== | |
667 | * SPA IO History Routines | |
668 | * ========================================================================== | |
669 | */ | |
670 | static int | |
671 | spa_io_history_update(kstat_t *ksp, int rw) | |
672 | { | |
673 | if (rw == KSTAT_WRITE) | |
674 | memset(ksp->ks_data, 0, ksp->ks_data_size); | |
675 | ||
676 | return (0); | |
677 | } | |
678 | ||
679 | static void | |
680 | spa_io_history_init(spa_t *spa) | |
681 | { | |
682 | spa_stats_history_t *ssh = &spa->spa_stats.io_history; | |
683 | char name[KSTAT_STRLEN]; | |
684 | kstat_t *ksp; | |
685 | ||
686 | mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL); | |
687 | ||
688 | (void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa)); | |
a08ee875 LG |
689 | |
690 | ksp = kstat_create(name, 0, "io", "disk", KSTAT_TYPE_IO, 1, 0); | |
691 | ssh->kstat = ksp; | |
692 | ||
693 | if (ksp) { | |
694 | ksp->ks_lock = &ssh->lock; | |
695 | ksp->ks_private = spa; | |
696 | ksp->ks_update = spa_io_history_update; | |
697 | kstat_install(ksp); | |
698 | } | |
699 | } | |
700 | ||
701 | static void | |
702 | spa_io_history_destroy(spa_t *spa) | |
703 | { | |
704 | spa_stats_history_t *ssh = &spa->spa_stats.io_history; | |
705 | ||
706 | if (ssh->kstat) | |
707 | kstat_delete(ssh->kstat); | |
708 | ||
709 | mutex_destroy(&ssh->lock); | |
710 | } | |
711 | ||
cae5b340 AX |
712 | /* |
713 | * ========================================================================== | |
714 | * SPA MMP History Routines | |
715 | * ========================================================================== | |
716 | */ | |
717 | ||
718 | /* | |
42f7b73b AX |
719 | * MMP statistics - Information exported regarding attempted MMP writes |
720 | * For MMP writes issued, fields used as per comments below. | |
721 | * For MMP writes skipped, an entry represents a span of time when | |
722 | * writes were skipped for same reason (error from mmp_random_leaf). | |
723 | * Differences are: | |
724 | * timestamp time first write skipped, if >1 skipped in a row | |
725 | * mmp_delay delay value at timestamp | |
726 | * vdev_guid number of writes skipped | |
727 | * io_error one of enum mmp_error | |
728 | * duration time span (ns) of skipped writes | |
cae5b340 AX |
729 | */ |
730 | ||
731 | typedef struct spa_mmp_history { | |
42f7b73b | 732 | uint64_t mmp_kstat_id; /* unique # for updates */ |
cae5b340 | 733 | uint64_t txg; /* txg of last sync */ |
42f7b73b AX |
734 | uint64_t timestamp; /* UTC time MMP write issued */ |
735 | uint64_t mmp_delay; /* mmp_thread.mmp_delay at timestamp */ | |
cae5b340 AX |
736 | uint64_t vdev_guid; /* unique ID of leaf vdev */ |
737 | char *vdev_path; | |
42f7b73b AX |
738 | int vdev_label; /* vdev label */ |
739 | int io_error; /* error status of MMP write */ | |
740 | hrtime_t error_start; /* hrtime of start of error period */ | |
741 | hrtime_t duration; /* time from submission to completion */ | |
cae5b340 AX |
742 | list_node_t smh_link; |
743 | } spa_mmp_history_t; | |
744 | ||
745 | static int | |
746 | spa_mmp_history_headers(char *buf, size_t size) | |
747 | { | |
42f7b73b AX |
748 | (void) snprintf(buf, size, "%-10s %-10s %-10s %-6s %-10s %-12s %-24s " |
749 | "%-10s %s\n", "id", "txg", "timestamp", "error", "duration", | |
750 | "mmp_delay", "vdev_guid", "vdev_label", "vdev_path"); | |
cae5b340 AX |
751 | return (0); |
752 | } | |
753 | ||
754 | static int | |
755 | spa_mmp_history_data(char *buf, size_t size, void *data) | |
756 | { | |
757 | spa_mmp_history_t *smh = (spa_mmp_history_t *)data; | |
42f7b73b AX |
758 | char skip_fmt[] = "%-10llu %-10llu %10llu %#6llx %10lld %12llu %-24llu " |
759 | "%-10lld %s\n"; | |
760 | char write_fmt[] = "%-10llu %-10llu %10llu %6lld %10lld %12llu %-24llu " | |
761 | "%-10lld %s\n"; | |
762 | ||
763 | (void) snprintf(buf, size, (smh->error_start ? skip_fmt : write_fmt), | |
764 | (u_longlong_t)smh->mmp_kstat_id, (u_longlong_t)smh->txg, | |
765 | (u_longlong_t)smh->timestamp, (longlong_t)smh->io_error, | |
766 | (longlong_t)smh->duration, (u_longlong_t)smh->mmp_delay, | |
767 | (u_longlong_t)smh->vdev_guid, (u_longlong_t)smh->vdev_label, | |
cae5b340 AX |
768 | (smh->vdev_path ? smh->vdev_path : "-")); |
769 | ||
770 | return (0); | |
771 | } | |
772 | ||
773 | /* | |
774 | * Calculate the address for the next spa_stats_history_t entry. The | |
775 | * ssh->lock will be held until ksp->ks_ndata entries are processed. | |
776 | */ | |
777 | static void * | |
778 | spa_mmp_history_addr(kstat_t *ksp, loff_t n) | |
779 | { | |
780 | spa_t *spa = ksp->ks_private; | |
781 | spa_stats_history_t *ssh = &spa->spa_stats.mmp_history; | |
782 | ||
783 | ASSERT(MUTEX_HELD(&ssh->lock)); | |
784 | ||
785 | if (n == 0) | |
786 | ssh->private = list_tail(&ssh->list); | |
787 | else if (ssh->private) | |
788 | ssh->private = list_prev(&ssh->list, ssh->private); | |
789 | ||
790 | return (ssh->private); | |
791 | } | |
792 | ||
793 | /* | |
794 | * When the kstat is written discard all spa_mmp_history_t entries. The | |
795 | * ssh->lock will be held until ksp->ks_ndata entries are processed. | |
796 | */ | |
797 | static int | |
798 | spa_mmp_history_update(kstat_t *ksp, int rw) | |
799 | { | |
800 | spa_t *spa = ksp->ks_private; | |
801 | spa_stats_history_t *ssh = &spa->spa_stats.mmp_history; | |
802 | ||
803 | ASSERT(MUTEX_HELD(&ssh->lock)); | |
804 | ||
805 | if (rw == KSTAT_WRITE) { | |
806 | spa_mmp_history_t *smh; | |
807 | ||
808 | while ((smh = list_remove_head(&ssh->list))) { | |
809 | ssh->size--; | |
810 | if (smh->vdev_path) | |
811 | strfree(smh->vdev_path); | |
812 | kmem_free(smh, sizeof (spa_mmp_history_t)); | |
813 | } | |
814 | ||
815 | ASSERT3U(ssh->size, ==, 0); | |
816 | } | |
817 | ||
818 | ksp->ks_ndata = ssh->size; | |
819 | ksp->ks_data_size = ssh->size * sizeof (spa_mmp_history_t); | |
820 | ||
821 | return (0); | |
822 | } | |
823 | ||
824 | static void | |
825 | spa_mmp_history_init(spa_t *spa) | |
826 | { | |
827 | spa_stats_history_t *ssh = &spa->spa_stats.mmp_history; | |
828 | char name[KSTAT_STRLEN]; | |
829 | kstat_t *ksp; | |
830 | ||
831 | mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL); | |
832 | list_create(&ssh->list, sizeof (spa_mmp_history_t), | |
833 | offsetof(spa_mmp_history_t, smh_link)); | |
834 | ||
835 | ssh->count = 0; | |
836 | ssh->size = 0; | |
837 | ssh->private = NULL; | |
838 | ||
839 | (void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa)); | |
840 | ||
841 | ksp = kstat_create(name, 0, "multihost", "misc", | |
842 | KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL); | |
843 | ssh->kstat = ksp; | |
844 | ||
845 | if (ksp) { | |
846 | ksp->ks_lock = &ssh->lock; | |
847 | ksp->ks_data = NULL; | |
848 | ksp->ks_private = spa; | |
849 | ksp->ks_update = spa_mmp_history_update; | |
850 | kstat_set_raw_ops(ksp, spa_mmp_history_headers, | |
851 | spa_mmp_history_data, spa_mmp_history_addr); | |
852 | kstat_install(ksp); | |
853 | } | |
854 | } | |
855 | ||
856 | static void | |
857 | spa_mmp_history_destroy(spa_t *spa) | |
858 | { | |
859 | spa_stats_history_t *ssh = &spa->spa_stats.mmp_history; | |
860 | spa_mmp_history_t *smh; | |
861 | kstat_t *ksp; | |
862 | ||
863 | ksp = ssh->kstat; | |
864 | if (ksp) | |
865 | kstat_delete(ksp); | |
866 | ||
867 | mutex_enter(&ssh->lock); | |
868 | while ((smh = list_remove_head(&ssh->list))) { | |
869 | ssh->size--; | |
870 | if (smh->vdev_path) | |
871 | strfree(smh->vdev_path); | |
872 | kmem_free(smh, sizeof (spa_mmp_history_t)); | |
873 | } | |
874 | ||
875 | ASSERT3U(ssh->size, ==, 0); | |
876 | list_destroy(&ssh->list); | |
877 | mutex_exit(&ssh->lock); | |
878 | ||
879 | mutex_destroy(&ssh->lock); | |
880 | } | |
881 | ||
882 | /* | |
42f7b73b AX |
883 | * Set duration in existing "skip" record to how long we have waited for a leaf |
884 | * vdev to become available. | |
885 | * | |
886 | * Important that we start search at the head of the list where new | |
887 | * records are inserted, so this is normally an O(1) operation. | |
cae5b340 | 888 | */ |
42f7b73b AX |
889 | int |
890 | spa_mmp_history_set_skip(spa_t *spa, uint64_t mmp_kstat_id) | |
891 | { | |
892 | spa_stats_history_t *ssh = &spa->spa_stats.mmp_history; | |
893 | spa_mmp_history_t *smh; | |
894 | int error = ENOENT; | |
895 | ||
896 | if (zfs_multihost_history == 0 && ssh->size == 0) | |
897 | return (0); | |
898 | ||
899 | mutex_enter(&ssh->lock); | |
900 | for (smh = list_head(&ssh->list); smh != NULL; | |
901 | smh = list_next(&ssh->list, smh)) { | |
902 | if (smh->mmp_kstat_id == mmp_kstat_id) { | |
903 | ASSERT3U(smh->io_error, !=, 0); | |
904 | smh->duration = gethrtime() - smh->error_start; | |
905 | smh->vdev_guid++; | |
906 | error = 0; | |
907 | break; | |
908 | } | |
909 | } | |
910 | mutex_exit(&ssh->lock); | |
911 | ||
912 | return (error); | |
913 | } | |
914 | ||
915 | /* | |
916 | * Set MMP write duration and error status in existing record. | |
917 | * See comment re: search order above spa_mmp_history_set_skip(). | |
918 | */ | |
919 | int | |
920 | spa_mmp_history_set(spa_t *spa, uint64_t mmp_kstat_id, int io_error, | |
921 | hrtime_t duration) | |
922 | { | |
923 | spa_stats_history_t *ssh = &spa->spa_stats.mmp_history; | |
924 | spa_mmp_history_t *smh; | |
925 | int error = ENOENT; | |
926 | ||
927 | if (zfs_multihost_history == 0 && ssh->size == 0) | |
928 | return (0); | |
929 | ||
930 | mutex_enter(&ssh->lock); | |
931 | for (smh = list_head(&ssh->list); smh != NULL; | |
932 | smh = list_next(&ssh->list, smh)) { | |
933 | if (smh->mmp_kstat_id == mmp_kstat_id) { | |
934 | ASSERT(smh->io_error == 0); | |
935 | smh->io_error = io_error; | |
936 | smh->duration = duration; | |
937 | error = 0; | |
938 | break; | |
939 | } | |
940 | } | |
941 | mutex_exit(&ssh->lock); | |
942 | ||
943 | return (error); | |
944 | } | |
945 | ||
946 | /* | |
947 | * Add a new MMP historical record. | |
948 | * error == 0 : a write was issued. | |
949 | * error != 0 : a write was not issued because no leaves were found. | |
950 | */ | |
951 | void * | |
952 | spa_mmp_history_add(spa_t *spa, uint64_t txg, uint64_t timestamp, | |
953 | uint64_t mmp_delay, vdev_t *vd, int label, uint64_t mmp_kstat_id, | |
954 | int error) | |
cae5b340 | 955 | { |
cae5b340 AX |
956 | spa_stats_history_t *ssh = &spa->spa_stats.mmp_history; |
957 | spa_mmp_history_t *smh, *rm; | |
958 | ||
959 | if (zfs_multihost_history == 0 && ssh->size == 0) | |
42f7b73b | 960 | return (NULL); |
cae5b340 AX |
961 | |
962 | smh = kmem_zalloc(sizeof (spa_mmp_history_t), KM_SLEEP); | |
963 | smh->txg = txg; | |
964 | smh->timestamp = timestamp; | |
965 | smh->mmp_delay = mmp_delay; | |
42f7b73b AX |
966 | if (vd) { |
967 | smh->vdev_guid = vd->vdev_guid; | |
968 | if (vd->vdev_path) | |
969 | smh->vdev_path = strdup(vd->vdev_path); | |
970 | } | |
cae5b340 | 971 | smh->vdev_label = label; |
42f7b73b AX |
972 | smh->mmp_kstat_id = mmp_kstat_id; |
973 | ||
974 | if (error) { | |
975 | smh->io_error = error; | |
976 | smh->error_start = gethrtime(); | |
977 | smh->vdev_guid = 1; | |
978 | } | |
cae5b340 AX |
979 | |
980 | mutex_enter(&ssh->lock); | |
981 | ||
982 | list_insert_head(&ssh->list, smh); | |
983 | ssh->size++; | |
984 | ||
985 | while (ssh->size > zfs_multihost_history) { | |
986 | ssh->size--; | |
987 | rm = list_remove_tail(&ssh->list); | |
988 | if (rm->vdev_path) | |
989 | strfree(rm->vdev_path); | |
990 | kmem_free(rm, sizeof (spa_mmp_history_t)); | |
991 | } | |
992 | ||
993 | mutex_exit(&ssh->lock); | |
42f7b73b | 994 | return ((void *)smh); |
cae5b340 AX |
995 | } |
996 | ||
a07c8b41 MZ |
997 | static void * |
998 | spa_state_addr(kstat_t *ksp, loff_t n) | |
999 | { | |
1000 | return (ksp->ks_private); /* return the spa_t */ | |
1001 | } | |
1002 | ||
1003 | static int | |
1004 | spa_state_data(char *buf, size_t size, void *data) | |
1005 | { | |
1006 | spa_t *spa = (spa_t *)data; | |
1007 | (void) snprintf(buf, size, "%s\n", spa_state_to_name(spa)); | |
1008 | return (0); | |
1009 | } | |
1010 | ||
1011 | /* | |
1012 | * Return the state of the pool in /proc/spl/kstat/zfs/<pool>/state. | |
1013 | * | |
1014 | * This is a lock-less read of the pool's state (unlike using 'zpool', which | |
1015 | * can potentially block for seconds). Because it doesn't block, it can useful | |
1016 | * as a pool heartbeat value. | |
1017 | */ | |
1018 | static void | |
1019 | spa_state_init(spa_t *spa) | |
1020 | { | |
1021 | spa_stats_history_t *ssh = &spa->spa_stats.state; | |
1022 | char *name; | |
1023 | kstat_t *ksp; | |
1024 | ||
1025 | mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL); | |
1026 | ||
1027 | name = kmem_asprintf("zfs/%s", spa_name(spa)); | |
1028 | ksp = kstat_create(name, 0, "state", "misc", | |
1029 | KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL); | |
1030 | ||
1031 | ssh->kstat = ksp; | |
1032 | if (ksp) { | |
1033 | ksp->ks_lock = &ssh->lock; | |
1034 | ksp->ks_data = NULL; | |
1035 | ksp->ks_private = spa; | |
1036 | ksp->ks_flags |= KSTAT_FLAG_NO_HEADERS; | |
1037 | kstat_set_raw_ops(ksp, NULL, spa_state_data, spa_state_addr); | |
1038 | kstat_install(ksp); | |
1039 | } | |
1040 | ||
1041 | strfree(name); | |
1042 | } | |
1043 | ||
1044 | static void | |
1045 | spa_health_destroy(spa_t *spa) | |
1046 | { | |
1047 | spa_stats_history_t *ssh = &spa->spa_stats.state; | |
1048 | kstat_t *ksp = ssh->kstat; | |
1049 | if (ksp) | |
1050 | kstat_delete(ksp); | |
1051 | ||
1052 | mutex_destroy(&ssh->lock); | |
1053 | } | |
1054 | ||
a08ee875 LG |
1055 | void |
1056 | spa_stats_init(spa_t *spa) | |
1057 | { | |
1058 | spa_read_history_init(spa); | |
1059 | spa_txg_history_init(spa); | |
1060 | spa_tx_assign_init(spa); | |
1061 | spa_io_history_init(spa); | |
cae5b340 | 1062 | spa_mmp_history_init(spa); |
a07c8b41 | 1063 | spa_state_init(spa); |
a08ee875 LG |
1064 | } |
1065 | ||
1066 | void | |
1067 | spa_stats_destroy(spa_t *spa) | |
1068 | { | |
a07c8b41 | 1069 | spa_health_destroy(spa); |
a08ee875 LG |
1070 | spa_tx_assign_destroy(spa); |
1071 | spa_txg_history_destroy(spa); | |
1072 | spa_read_history_destroy(spa); | |
1073 | spa_io_history_destroy(spa); | |
cae5b340 | 1074 | spa_mmp_history_destroy(spa); |
a08ee875 LG |
1075 | } |
1076 | ||
1077 | #if defined(_KERNEL) && defined(HAVE_SPL) | |
cae5b340 | 1078 | /* CSTYLED */ |
a08ee875 | 1079 | module_param(zfs_read_history, int, 0644); |
cae5b340 AX |
1080 | MODULE_PARM_DESC(zfs_read_history, |
1081 | "Historical statistics for the last N reads"); | |
a08ee875 LG |
1082 | |
1083 | module_param(zfs_read_history_hits, int, 0644); | |
cae5b340 AX |
1084 | MODULE_PARM_DESC(zfs_read_history_hits, |
1085 | "Include cache hits in read history"); | |
a08ee875 LG |
1086 | |
1087 | module_param(zfs_txg_history, int, 0644); | |
cae5b340 AX |
1088 | MODULE_PARM_DESC(zfs_txg_history, |
1089 | "Historical statistics for the last N txgs"); | |
1090 | ||
1091 | module_param(zfs_multihost_history, int, 0644); | |
1092 | MODULE_PARM_DESC(zfs_multihost_history, | |
1093 | "Historical statistics for last N multihost writes"); | |
1094 | /* END CSTYLED */ | |
a08ee875 | 1095 | #endif |