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>
38 #if defined(KERNEL_LINUX)
39 #include "utils_llist.h"
40 #define ZOL_ARCSTATS_FILE "/proc/spl/kstat/zfs/arcstats"
42 typedef llist_t kstat_t;
44 static long long get_zfs_value(kstat_t *zfs_stats __attribute__((unused)),
49 e = llist_search (zfs_stats, name);
52 ERROR ("zfs_arc plugin: `llist_search` failed for key: '%s'.", name);
56 return (*(long long int*)e->value);
59 #elif !defined(__FreeBSD__) // Solaris
60 extern kstat_ctl_t *kc;
62 static long long get_zfs_value(kstat_t *ksp, char *name)
65 return (get_kstat_value(ksp, name));
68 #include <sys/types.h>
69 #include <sys/sysctl.h>
71 const char zfs_arcstat[] = "kstat.zfs.misc.arcstats.";
77 static long long get_zfs_value(kstat_t *dummy __attribute__((unused)),
82 size_t valuelen = sizeof(value);
85 ssnprintf (buffer, sizeof (buffer), "%s%s", zfs_arcstat, name);
86 rv = sysctlbyname (buffer, (void *) &value, &valuelen,
87 /* new value = */ NULL, /* new length = */ (size_t) 0);
95 static void za_submit (const char* type, const char* type_instance, value_t* values, int values_len)
97 value_list_t vl = VALUE_LIST_INIT;
100 vl.values_len = values_len;
102 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
103 sstrncpy (vl.plugin, "zfs_arc", sizeof (vl.plugin));
104 sstrncpy (vl.type, type, sizeof (vl.type));
105 sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
107 plugin_dispatch_values (&vl);
110 static void za_submit_gauge (const char* type, const char* type_instance, gauge_t value)
115 za_submit (type, type_instance, &vv, 1);
118 static int za_read_derive (kstat_t *ksp, const char *kstat_value,
119 const char *type, const char *type_instance)
124 tmp = get_zfs_value (ksp, (char *)kstat_value);
127 WARNING ("zfs_arc plugin: Reading kstat value \"%s\" failed.", kstat_value);
131 v.derive = (derive_t) tmp;
132 za_submit (type, type_instance, /* values = */ &v, /* values_num = */ 1);
136 static int za_read_gauge (kstat_t *ksp, const char *kstat_value,
137 const char *type, const char *type_instance)
142 tmp = get_zfs_value (ksp, (char *)kstat_value);
145 WARNING ("zfs_arc plugin: Reading kstat value \"%s\" failed.", kstat_value);
149 v.gauge = (gauge_t) tmp;
150 za_submit (type, type_instance, /* values = */ &v, /* values_num = */ 1);
154 static void za_submit_ratio (const char* type_instance, gauge_t hits, gauge_t misses)
158 if (!isfinite (hits) || (hits < 0.0))
160 if (!isfinite (misses) || (misses < 0.0))
163 if ((hits != 0.0) || (misses != 0.0))
164 ratio = hits / (hits + misses);
166 za_submit_gauge ("cache_ratio", type_instance, ratio);
169 static int za_read (void)
171 gauge_t arc_hits, arc_misses, l2_hits, l2_misses;
176 long long int *llvalues = NULL;
177 char file_contents[1024 * 10];
182 ksp = llist_create ();
185 ERROR ("zfs_arc plugin: `llist_create' failed.");
189 len = read_file_contents (ZOL_ARCSTATS_FILE, file_contents, sizeof(file_contents));
194 char *pnl = file_contents;
197 file_contents[len] = '\0';
201 pnl = strchr(pnl, '\n');
203 if (pnl && (*pnl != '\0'))
210 llvalues = malloc(sizeof(long long int) * i);
216 pnnl = strchr(pnl, '\n');
220 numfields = strsplit (pnl, fields, 4);
223 llvalues[j] = atoll (fields[2]);
225 e = llentry_create (fields[0], &llvalues[j]);
228 ERROR ("zfs_arc plugin: `llentry_create' failed.");
232 llist_append (ksp, e);
243 #elif !defined(__FreeBSD__) // Solaris
244 get_kstat (&ksp, "zfs", 0, "arcstats");
247 ERROR ("zfs_arc plugin: Cannot find zfs:0:arcstats kstat.");
253 za_read_gauge (ksp, "size", "cache_size", "arc");
254 za_read_gauge (ksp, "c", "cache_size", "c");
255 za_read_gauge (ksp, "c_min", "cache_size", "c_min");
256 za_read_gauge (ksp, "c_max", "cache_size", "c_max");
258 /* The "l2_size" value has disappeared from Solaris some time in
259 * early 2013, and has only reappeared recently in Solaris 11.2.
260 * Stop trying if we ever fail to read it, so we don't spam the log.
262 static int l2_size_avail = 1;
263 if (l2_size_avail && za_read_gauge (ksp, "l2_size", "cache_size", "L2") != 0)
267 za_read_derive (ksp, "deleted", "cache_operation", "deleted");
269 za_read_derive (ksp, "allocated","cache_operation", "allocated");
270 za_read_derive (ksp, "stolen", "cache_operation", "stolen");
273 /* Issue indicators */
274 za_read_derive (ksp, "mutex_miss", "mutex_operations", "miss");
275 za_read_derive (ksp, "hash_collisions", "hash_collisions", "");
278 za_read_derive (ksp, "evict_l2_cached", "cache_eviction", "cached");
279 za_read_derive (ksp, "evict_l2_eligible", "cache_eviction", "eligible");
280 za_read_derive (ksp, "evict_l2_ineligible", "cache_eviction", "ineligible");
283 za_read_derive (ksp, "demand_data_hits", "cache_result", "demand_data-hit");
284 za_read_derive (ksp, "demand_metadata_hits", "cache_result", "demand_metadata-hit");
285 za_read_derive (ksp, "prefetch_data_hits", "cache_result", "prefetch_data-hit");
286 za_read_derive (ksp, "prefetch_metadata_hits", "cache_result", "prefetch_metadata-hit");
287 za_read_derive (ksp, "demand_data_misses", "cache_result", "demand_data-miss");
288 za_read_derive (ksp, "demand_metadata_misses", "cache_result", "demand_metadata-miss");
289 za_read_derive (ksp, "prefetch_data_misses", "cache_result", "prefetch_data-miss");
290 za_read_derive (ksp, "prefetch_metadata_misses", "cache_result", "prefetch_metadata-miss");
293 arc_hits = (gauge_t) get_zfs_value(ksp, "hits");
294 arc_misses = (gauge_t) get_zfs_value(ksp, "misses");
295 l2_hits = (gauge_t) get_zfs_value(ksp, "l2_hits");
296 l2_misses = (gauge_t) get_zfs_value(ksp, "l2_misses");
298 za_submit_ratio ("arc", arc_hits, arc_misses);
299 za_submit_ratio ("L2", l2_hits, l2_misses);
302 l2_io[0].derive = get_zfs_value(ksp, "l2_read_bytes");
303 l2_io[1].derive = get_zfs_value(ksp, "l2_write_bytes");
305 za_submit ("io_octets", "L2", l2_io, /* num values = */ 2);
307 #if defined(KERNEL_LINUX)
308 if (llvalues != NULL)
321 static int za_init (void) /* {{{ */
323 #if !defined(__FreeBSD__) && !defined(KERNEL_LINUX) // Solaris
324 /* kstats chain already opened by update_kstat (using *kc), verify everything went fine. */
327 ERROR ("zfs_arc plugin: kstat chain control structure not available.");
333 } /* }}} int za_init */
335 void module_register (void)
337 plugin_register_init ("zfs_arc", za_init);
338 plugin_register_read ("zfs_arc", za_read);
339 } /* void module_register */
341 /* vmi: set sw=8 noexpandtab fdm=marker : */