ea05bf89305aed3cfbaddcabb6531b18b191019a
1 /**
2 * collectd - src/zfs_arc.c
3 * Copyright (C) 2009 Anthony Dewhurst
4 * Copyright (C) 2012 Aurelien Rougemont
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; only version 2 of the License is applicable.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors:
20 * Anthony Dewhurst <dewhurst at gmail>
21 * Aurelien Rougemont <beorn at gandi.net>
22 **/
24 #include "collectd.h"
25 #include "common.h"
26 #include "plugin.h"
28 /*
29 * Global variables
30 */
31 static kstat_t *ksp;
32 extern kstat_ctl_t *kc;
34 static void za_submit (const char* type, const char* type_instance, value_t* values, int values_len)
35 {
36 value_list_t vl = VALUE_LIST_INIT;
38 vl.values = values;
39 vl.values_len = values_len;
41 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
42 sstrncpy (vl.plugin, "zfs_arc", sizeof (vl.plugin));
43 sstrncpy (vl.type, type, sizeof (vl.type));
44 sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
46 plugin_dispatch_values (&vl);
47 }
49 static void za_submit_gauge (const char* type, const char* type_instance, gauge_t value)
50 {
51 value_t vv;
53 vv.gauge = value;
54 za_submit (type, type_instance, &vv, 1);
55 }
57 static void za_submit_derive (const char* type, const char* type_instance, derive_t dv)
58 {
59 value_t vv;
61 vv.derive = dv;
62 za_submit (type, type_instance, &vv, 1);
63 }
65 static void za_submit_ratio (const char* type_instance, gauge_t hits, gauge_t misses)
66 {
67 gauge_t ratio = NAN;
69 if (!isfinite (hits) || (hits < 0.0))
70 hits = 0.0;
71 if (!isfinite (misses) || (misses < 0.0))
72 misses = 0.0;
74 if ((hits != 0.0) || (misses != 0.0))
75 ratio = hits / (hits + misses);
77 za_submit_gauge ("cache_ratio", type_instance, ratio);
78 }
80 static int za_read (void)
81 {
82 gauge_t arc_size, l2_size;
83 derive_t demand_data_hits,
84 demand_metadata_hits,
85 prefetch_data_hits,
86 prefetch_metadata_hits,
87 demand_data_misses,
88 demand_metadata_misses,
89 prefetch_data_misses,
90 prefetch_metadata_misses;
91 gauge_t arc_hits, arc_misses, l2_hits, l2_misses;
92 value_t l2_io[2];
93 derive_t mutex_miss;
94 derive_t allocated, deleted, stolen;
95 derive_t evict_l2_cached, evict_l2_eligible, evict_l2_ineligible;
96 derive_t hash_collisions;
98 get_kstat (&ksp, "zfs", 0, "arcstats");
99 if (ksp == NULL)
100 {
101 ERROR ("zfs_arc plugin: Cannot find zfs:0:arcstats kstat.");
102 return (-1);
103 }
105 /* Sizes */
106 arc_size = get_kstat_value(ksp, "size");
107 l2_size = get_kstat_value(ksp, "l2_size");
109 za_submit_gauge ("cache_size", "arc", arc_size);
110 za_submit_gauge ("cache_size", "L2", l2_size);
112 mutex_miss = get_kstat_value (ksp, "mutex_miss");
113 za_submit_derive ("mutex_operation", "miss", mutex_miss);
115 allocated = get_kstat_value(ksp, "allocated");
116 deleted = get_kstat_value(ksp, "deleted");
117 stolen = get_kstat_value(ksp, "stolen");
118 za_submit_derive ("cache_operation", "allocated", allocated);
119 za_submit_derive ("cache_operation", "deleted", deleted);
120 za_submit_derive ("cache_operation", "stolen", stolen);
122 hash_collisions = get_kstat_value(ksp, "hash_collisions");
123 za_submit_derive ("hash_collisions", "", hash_collisions);
125 evict_l2_cached = get_kstat_value(ksp, "evict_l2_cached");
126 evict_l2_eligible = get_kstat_value(ksp, "evict_l2_eligible");
127 evict_l2_ineligible = get_kstat_value(ksp, "evict_l2_ineligible");
129 za_submit_derive ("cache_eviction", "cached", evict_l2_cached);
130 za_submit_derive ("cache_eviction", "eligible", evict_l2_eligible);
131 za_submit_derive ("cache_eviction", "ineligible", evict_l2_ineligible);
133 /* Hits / misses */
134 demand_data_hits = get_kstat_value(ksp, "demand_data_hits");
135 demand_metadata_hits = get_kstat_value(ksp, "demand_metadata_hits");
136 prefetch_data_hits = get_kstat_value(ksp, "prefetch_data_hits");
137 prefetch_metadata_hits = get_kstat_value(ksp, "prefetch_metadata_hits");
139 demand_data_misses = get_kstat_value(ksp, "demand_data_misses");
140 demand_metadata_misses = get_kstat_value(ksp, "demand_metadata_misses");
141 prefetch_data_misses = get_kstat_value(ksp, "prefetch_data_misses");
142 prefetch_metadata_misses = get_kstat_value(ksp, "prefetch_metadata_misses");
144 za_submit_derive ("cache_result", "demand_data-hit", demand_data_hits);
145 za_submit_derive ("cache_result", "demand_metadata-hit", demand_metadata_hits);
146 za_submit_derive ("cache_result", "prefetch_data-hit", prefetch_data_hits);
147 za_submit_derive ("cache_result", "prefetch_metadata-hit", prefetch_metadata_hits);
149 za_submit_derive ("cache_result", "demand_data-miss", demand_data_misses);
150 za_submit_derive ("cache_result", "demand_metadata-miss", demand_metadata_misses);
151 za_submit_derive ("cache_result", "prefetch_data-miss", prefetch_data_misses);
152 za_submit_derive ("cache_result", "prefetch_metadata-miss", prefetch_metadata_misses);
154 /* Ratios */
155 arc_hits = (gauge_t) get_kstat_value(ksp, "hits");
156 arc_misses = (gauge_t) get_kstat_value(ksp, "misses");
157 l2_hits = (gauge_t) get_kstat_value(ksp, "l2_hits");
158 l2_misses = (gauge_t) get_kstat_value(ksp, "l2_misses");
160 za_submit_ratio ("arc", arc_hits, arc_misses);
161 za_submit_ratio ("L2", l2_hits, l2_misses);
163 /* I/O */
164 l2_io[0].derive = get_kstat_value(ksp, "l2_read_bytes");
165 l2_io[1].derive = get_kstat_value(ksp, "l2_write_bytes");
167 za_submit ("io_octets", "L2", l2_io, /* num values = */ 2);
169 return (0);
170 } /* int za_read */
172 static int za_init (void) /* {{{ */
173 {
174 ksp = NULL;
176 /* kstats chain already opened by update_kstat (using *kc), verify everything went fine. */
177 if (kc == NULL)
178 {
179 ERROR ("zfs_arc plugin: kstat chain control structure not available.");
180 return (-1);
181 }
183 return (0);
184 } /* }}} int za_init */
186 void module_register (void)
187 {
188 plugin_register_init ("zfs_arc", za_init);
189 plugin_register_read ("zfs_arc", za_read);
190 } /* void module_register */
192 /* vmi: set sw=8 noexpandtab fdm=marker : */