2 * collectd - src/zfs_arc.c
3 * Copyright (C) 2009 Anthony Dewhurst
4 * Copyright (C) 2012 Aurelien Rougemont
5 * Copyright (C) 2013 Xin Li
6 * Copyright (C) 2014 Marc Fournier
7 * Copyright (C) 2014 Wilfried Goesgens
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; only version 2 of the License is applicable.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
23 * Anthony Dewhurst <dewhurst at gmail>
24 * Aurelien Rougemont <beorn at gandi.net>
25 * Xin Li <delphij at FreeBSD.org>
26 * Marc Fournier <marc.fournier at camptocamp.com>
27 * Wilfried Goesgens <dothebart at citadel.org>
39 #if defined(KERNEL_LINUX)
40 #include "utils_llist.h"
41 #define ZOL_ARCSTATS_FILE "/proc/spl/kstat/zfs/arcstats"
43 typedef llist_t kstat_t;
45 static int put_zfs_value(kstat_t *ksp, char const *k, value_t v) {
54 v_copy = malloc(sizeof(*v_copy));
61 e = llentry_create(k_copy, v_copy);
72 static long long get_zfs_value(kstat_t *ksp, const char *key) {
76 e = llist_search(ksp, key);
78 ERROR("zfs_arc plugin: `llist_search` failed for key: '%s'.", key);
83 return ((long long)v->derive);
86 static void free_zfs_values(kstat_t *ksp) {
90 for (llentry_t *e = llist_head(ksp); e != NULL; e = e->next) {
98 #elif defined(KERNEL_SOLARIS)
99 extern kstat_ctl_t *kc;
101 static long long get_zfs_value(kstat_t *ksp, char *name) {
103 return (get_kstat_value(ksp, name));
105 #elif defined(KERNEL_FREEBSD)
106 #include <sys/sysctl.h>
107 #include <sys/types.h>
109 const char zfs_arcstat[] = "kstat.zfs.misc.arcstats.";
111 #if !defined(kstat_t)
112 typedef void kstat_t;
115 static long long get_zfs_value(kstat_t *dummy __attribute__((unused)),
119 size_t valuelen = sizeof(value);
122 ssnprintf(buffer, sizeof(buffer), "%s%s", zfs_arcstat, name);
123 rv = sysctlbyname(buffer, (void *)&value, &valuelen,
124 /* new value = */ NULL, /* new length = */ (size_t)0);
132 static void za_submit(const char *type, const char *type_instance,
133 value_t *values, size_t values_len) {
134 value_list_t vl = VALUE_LIST_INIT;
137 vl.values_len = values_len;
139 sstrncpy(vl.plugin, "zfs_arc", sizeof(vl.plugin));
140 sstrncpy(vl.type, type, sizeof(vl.type));
141 sstrncpy(vl.type_instance, type_instance, sizeof(vl.type_instance));
143 plugin_dispatch_values(&vl);
146 static void za_submit_gauge(const char *type, const char *type_instance,
148 za_submit(type, type_instance, &(value_t){.gauge = value}, 1);
151 static int za_read_derive(kstat_t *ksp, const char *kstat_value,
152 const char *type, const char *type_instance) {
153 long long tmp = get_zfs_value(ksp, (char *)kstat_value);
155 WARNING("zfs_arc plugin: Reading kstat value \"%s\" failed.", kstat_value);
159 za_submit(type, type_instance, &(value_t){.derive = (derive_t)tmp},
160 /* values_num = */ 1);
164 static int za_read_gauge(kstat_t *ksp, const char *kstat_value,
165 const char *type, const char *type_instance) {
166 long long tmp = get_zfs_value(ksp, (char *)kstat_value);
168 WARNING("zfs_arc plugin: Reading kstat value \"%s\" failed.", kstat_value);
172 za_submit(type, type_instance, &(value_t){.gauge = (gauge_t)tmp},
173 /* values_num = */ 1);
177 static void za_submit_ratio(const char *type_instance, gauge_t hits,
181 if (!isfinite(hits) || (hits < 0.0))
183 if (!isfinite(misses) || (misses < 0.0))
186 if ((hits != 0.0) || (misses != 0.0))
187 ratio = hits / (hits + misses);
189 za_submit_gauge("cache_ratio", type_instance, ratio);
192 static int za_read(void) {
193 gauge_t arc_hits, arc_misses, l2_hits, l2_misses;
196 #if defined(KERNEL_LINUX)
200 fh = fopen(ZOL_ARCSTATS_FILE, "r");
203 ERROR("zfs_arc plugin: Opening \"%s\" failed: %s", ZOL_ARCSTATS_FILE,
204 sstrerror(errno, errbuf, sizeof(errbuf)));
208 ksp = llist_create();
210 ERROR("zfs_arc plugin: `llist_create' failed.");
215 while (fgets(buffer, sizeof(buffer), fh) != NULL) {
220 status = strsplit(buffer, fields, STATIC_ARRAY_SIZE(fields));
224 status = parse_value(fields[2], &v, DS_TYPE_DERIVE);
228 put_zfs_value(ksp, fields[0], v);
233 #elif defined(KERNEL_SOLARIS)
234 get_kstat(&ksp, "zfs", 0, "arcstats");
236 ERROR("zfs_arc plugin: Cannot find zfs:0:arcstats kstat.");
242 za_read_gauge(ksp, "anon_size", "cache_size", "anon_size");
243 za_read_gauge(ksp, "c", "cache_size", "c");
244 za_read_gauge(ksp, "c_max", "cache_size", "c_max");
245 za_read_gauge(ksp, "c_min", "cache_size", "c_min");
246 za_read_gauge(ksp, "hdr_size", "cache_size", "hdr_size");
247 za_read_gauge(ksp, "metadata_size", "cache_size", "metadata_size");
248 za_read_gauge(ksp, "mfu_ghost_size", "cache_size", "mfu_ghost_size");
249 za_read_gauge(ksp, "mfu_size", "cache_size", "mfu_size");
250 za_read_gauge(ksp, "mru_ghost_size", "cache_size", "mru_ghost_size");
251 za_read_gauge(ksp, "mru_size", "cache_size", "mru_size");
252 za_read_gauge(ksp, "other_size", "cache_size", "other_size");
253 za_read_gauge(ksp, "p", "cache_size", "p");
254 za_read_gauge(ksp, "size", "cache_size", "arc");
256 /* The "l2_size" value has disappeared from Solaris some time in
257 * early 2013, and has only reappeared recently in Solaris 11.2.
258 * Stop trying if we ever fail to read it, so we don't spam the log.
260 static int l2_size_avail = 1;
261 if (l2_size_avail && za_read_gauge(ksp, "l2_size", "cache_size", "L2") != 0)
265 za_read_derive(ksp, "deleted", "cache_operation", "deleted");
266 #if defined(KERNEL_FREEBSD)
267 za_read_derive(ksp, "allocated", "cache_operation", "allocated");
270 /* Issue indicators */
271 za_read_derive(ksp, "mutex_miss", "mutex_operations", "miss");
272 za_read_derive(ksp, "hash_collisions", "hash_collisions", "");
273 za_read_derive(ksp, "memory_throttle_count", "memory_throttle_count", "");
276 za_read_derive(ksp, "evict_l2_cached", "cache_eviction", "cached");
277 za_read_derive(ksp, "evict_l2_eligible", "cache_eviction", "eligible");
278 za_read_derive(ksp, "evict_l2_ineligible", "cache_eviction", "ineligible");
281 za_read_derive(ksp, "demand_data_hits", "cache_result", "demand_data-hit");
282 za_read_derive(ksp, "demand_metadata_hits", "cache_result",
283 "demand_metadata-hit");
284 za_read_derive(ksp, "prefetch_data_hits", "cache_result",
285 "prefetch_data-hit");
286 za_read_derive(ksp, "prefetch_metadata_hits", "cache_result",
287 "prefetch_metadata-hit");
288 za_read_derive(ksp, "demand_data_misses", "cache_result", "demand_data-miss");
289 za_read_derive(ksp, "demand_metadata_misses", "cache_result",
290 "demand_metadata-miss");
291 za_read_derive(ksp, "prefetch_data_misses", "cache_result",
292 "prefetch_data-miss");
293 za_read_derive(ksp, "prefetch_metadata_misses", "cache_result",
294 "prefetch_metadata-miss");
295 za_read_derive(ksp, "mfu_hits", "cache_result", "mfu-hit");
296 za_read_derive(ksp, "mfu_ghost_hits", "cache_result", "mfu_ghost-hit");
297 za_read_derive(ksp, "mru_hits", "cache_result", "mru-hit");
298 za_read_derive(ksp, "mru_ghost_hits", "cache_result", "mru_ghost-hit");
301 arc_hits = (gauge_t)get_zfs_value(ksp, "hits");
302 arc_misses = (gauge_t)get_zfs_value(ksp, "misses");
303 l2_hits = (gauge_t)get_zfs_value(ksp, "l2_hits");
304 l2_misses = (gauge_t)get_zfs_value(ksp, "l2_misses");
306 za_submit_ratio("arc", arc_hits, arc_misses);
307 za_submit_ratio("L2", l2_hits, l2_misses);
311 {.derive = (derive_t)get_zfs_value(ksp, "l2_read_bytes")},
312 {.derive = (derive_t)get_zfs_value(ksp, "l2_write_bytes")},
314 za_submit("io_octets", "L2", l2_io, STATIC_ARRAY_SIZE(l2_io));
316 #if defined(KERNEL_LINUX)
317 free_zfs_values(ksp);
323 static int za_init(void) /* {{{ */
325 #if defined(KERNEL_SOLARIS)
326 /* kstats chain already opened by update_kstat (using *kc), verify everything
329 ERROR("zfs_arc plugin: kstat chain control structure not available.");
335 } /* }}} int za_init */
337 void module_register(void) {
338 plugin_register_init("zfs_arc", za_init);
339 plugin_register_read("zfs_arc", za_read);
340 } /* void module_register */
342 /* vmi: set sw=8 noexpandtab fdm=marker : */