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diff --git a/src/zfs_arc.c b/src/zfs_arc.c
--- /dev/null
+++ b/src/zfs_arc.c
@@ -0,0 +1,338 @@
+/**
+ * collectd - src/zfs_arc.c
+ * Copyright (C) 2009 Anthony Dewhurst
+ * Copyright (C) 2012 Aurelien Rougemont
+ * Copyright (C) 2013 Xin Li
+ * Copyright (C) 2014 Marc Fournier
+ * Copyright (C) 2014 Wilfried Goesgens
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; only version 2 of the License is applicable.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors:
+ * Anthony Dewhurst <dewhurst at gmail>
+ * Aurelien Rougemont <beorn at gandi.net>
+ * Xin Li <delphij at FreeBSD.org>
+ * Marc Fournier <marc.fournier at camptocamp.com>
+ * Wilfried Goesgens <dothebart at citadel.org>
+ **/
+
+#include "collectd.h"
+#include "common.h"
+#include "plugin.h"
+
+/*
+ * Global variables
+ */
+
+#if defined(KERNEL_LINUX)
+#include "utils_llist.h"
+#define ZOL_ARCSTATS_FILE "/proc/spl/kstat/zfs/arcstats"
+
+typedef llist_t kstat_t;
+
+static long long get_zfs_value(kstat_t *zfs_stats __attribute__((unused)),
+ char *name)
+{
+ llentry_t *e;
+
+ e = llist_search (zfs_stats, name);
+ if (e == NULL)
+ {
+ ERROR ("zfs_arc plugin: `llist_search` failed for key: '%s'.", name);
+ return (-1);
+ }
+
+ return (*(long long int*)e->value);
+}
+
+#elif !defined(__FreeBSD__) // Solaris
+extern kstat_ctl_t *kc;
+
+static long long get_zfs_value(kstat_t *ksp, char *name)
+{
+
+ return (get_kstat_value(ksp, name));
+}
+#else // FreeBSD
+#include <sys/types.h>
+#include <sys/sysctl.h>
+
+const char zfs_arcstat[] = "kstat.zfs.misc.arcstats.";
+
+#if !defined(kstat_t)
+typedef void kstat_t;
+#endif
+
+static long long get_zfs_value(kstat_t *dummy __attribute__((unused)),
+ char const *name)
+{
+ char buffer[256];
+ long long value;
+ size_t valuelen = sizeof(value);
+ int rv;
+
+ ssnprintf (buffer, sizeof (buffer), "%s%s", zfs_arcstat, name);
+ rv = sysctlbyname (buffer, (void *) &value, &valuelen,
+ /* new value = */ NULL, /* new length = */ (size_t) 0);
+ if (rv == 0)
+ return (value);
+
+ return (-1);
+}
+#endif
+
+static void za_submit (const char* type, const char* type_instance, value_t* values, int values_len)
+{
+ value_list_t vl = VALUE_LIST_INIT;
+
+ vl.values = values;
+ vl.values_len = values_len;
+
+ sstrncpy (vl.host, hostname_g, sizeof (vl.host));
+ sstrncpy (vl.plugin, "zfs_arc", sizeof (vl.plugin));
+ sstrncpy (vl.type, type, sizeof (vl.type));
+ sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
+
+ plugin_dispatch_values (&vl);
+}
+
+static void za_submit_gauge (const char* type, const char* type_instance, gauge_t value)
+{
+ value_t vv;
+
+ vv.gauge = value;
+ za_submit (type, type_instance, &vv, 1);
+}
+
+static int za_read_derive (kstat_t *ksp, const char *kstat_value,
+ const char *type, const char *type_instance)
+{
+ long long tmp;
+ value_t v;
+
+ tmp = get_zfs_value (ksp, (char *)kstat_value);
+ if (tmp == -1LL)
+ {
+ WARNING ("zfs_arc plugin: Reading kstat value \"%s\" failed.", kstat_value);
+ return (-1);
+ }
+
+ v.derive = (derive_t) tmp;
+ za_submit (type, type_instance, /* values = */ &v, /* values_num = */ 1);
+ return (0);
+}
+
+static int za_read_gauge (kstat_t *ksp, const char *kstat_value,
+ const char *type, const char *type_instance)
+{
+ long long tmp;
+ value_t v;
+
+ tmp = get_zfs_value (ksp, (char *)kstat_value);
+ if (tmp == -1LL)
+ {
+ WARNING ("zfs_arc plugin: Reading kstat value \"%s\" failed.", kstat_value);
+ return (-1);
+ }
+
+ v.gauge = (gauge_t) tmp;
+ za_submit (type, type_instance, /* values = */ &v, /* values_num = */ 1);
+ return (0);
+}
+
+static void za_submit_ratio (const char* type_instance, gauge_t hits, gauge_t misses)
+{
+ gauge_t ratio = NAN;
+
+ if (!isfinite (hits) || (hits < 0.0))
+ hits = 0.0;
+ if (!isfinite (misses) || (misses < 0.0))
+ misses = 0.0;
+
+ if ((hits != 0.0) || (misses != 0.0))
+ ratio = hits / (hits + misses);
+
+ za_submit_gauge ("cache_ratio", type_instance, ratio);
+}
+
+static int za_read (void)
+{
+ gauge_t arc_hits, arc_misses, l2_hits, l2_misses;
+ value_t l2_io[2];
+ kstat_t *ksp = NULL;
+
+#if KERNEL_LINUX
+ long long int *llvalues = NULL;
+ char file_contents[1024 * 10];
+ char *fields[3];
+ int numfields;
+ ssize_t len;
+
+ ksp = llist_create ();
+ if (ksp == NULL)
+ {
+ ERROR ("zfs_arc plugin: `llist_create' failed.");
+ return (-1);
+ }
+
+ len = read_file_contents (ZOL_ARCSTATS_FILE, file_contents, sizeof(file_contents));
+ if (len > 1)
+ {
+
+ int i=0;
+ char *pnl = file_contents;
+ char *pnnl;
+
+ file_contents[len] = '\0';
+
+ while (pnl != NULL)
+ {
+ pnl = strchr(pnl, '\n');
+ i++;
+ if (pnl && (*pnl != '\0'))
+ pnl++;
+ }
+
+ if (i > 0)
+ {
+ llentry_t *e;
+ llvalues = malloc(sizeof(long long int) * i);
+ int j = 0;
+
+ pnl = file_contents;
+ while (pnl != NULL)
+ {
+ pnnl = strchr(pnl, '\n');
+ if (pnnl != NULL)
+ *pnnl = '\0';
+
+ numfields = strsplit (pnl, fields, 4);
+ if (numfields == 3)
+ {
+ llvalues[j] = atoll (fields[2]);
+
+ e = llentry_create (fields[0], &llvalues[j]);
+ if (e == NULL)
+ {
+ ERROR ("zfs_arc plugin: `llentry_create' failed.");
+ }
+ else
+ {
+ llist_append (ksp, e);
+ }
+ j++;
+ }
+ pnl = pnnl;
+ if (pnl != NULL)
+ pnl ++;
+ }
+ }
+ }
+
+#elif !defined(__FreeBSD__) // Solaris
+ get_kstat (&ksp, "zfs", 0, "arcstats");
+ if (ksp == NULL)
+ {
+ ERROR ("zfs_arc plugin: Cannot find zfs:0:arcstats kstat.");
+ return (-1);
+ }
+#endif
+
+ /* Sizes */
+ za_read_gauge (ksp, "size", "cache_size", "arc");
+
+ /* The "l2_size" value has disappeared from Solaris some time in
+ * early 2013, and has only reappeared recently in Solaris 11.2.
+ * Stop trying if we ever fail to read it, so we don't spam the log.
+ */
+ static int l2_size_avail = 1;
+ if (l2_size_avail && za_read_gauge (ksp, "l2_size", "cache_size", "L2") != 0)
+ l2_size_avail = 0;
+
+ /* Operations */
+ za_read_derive (ksp, "deleted", "cache_operation", "deleted");
+#if __FreeBSD__
+ za_read_derive (ksp, "allocated","cache_operation", "allocated");
+ za_read_derive (ksp, "stolen", "cache_operation", "stolen");
+#endif
+
+ /* Issue indicators */
+ za_read_derive (ksp, "mutex_miss", "mutex_operations", "miss");
+ za_read_derive (ksp, "hash_collisions", "hash_collisions", "");
+
+ /* Evictions */
+ za_read_derive (ksp, "evict_l2_cached", "cache_eviction", "cached");
+ za_read_derive (ksp, "evict_l2_eligible", "cache_eviction", "eligible");
+ za_read_derive (ksp, "evict_l2_ineligible", "cache_eviction", "ineligible");
+
+ /* Hits / misses */
+ za_read_derive (ksp, "demand_data_hits", "cache_result", "demand_data-hit");
+ za_read_derive (ksp, "demand_metadata_hits", "cache_result", "demand_metadata-hit");
+ za_read_derive (ksp, "prefetch_data_hits", "cache_result", "prefetch_data-hit");
+ za_read_derive (ksp, "prefetch_metadata_hits", "cache_result", "prefetch_metadata-hit");
+ za_read_derive (ksp, "demand_data_misses", "cache_result", "demand_data-miss");
+ za_read_derive (ksp, "demand_metadata_misses", "cache_result", "demand_metadata-miss");
+ za_read_derive (ksp, "prefetch_data_misses", "cache_result", "prefetch_data-miss");
+ za_read_derive (ksp, "prefetch_metadata_misses", "cache_result", "prefetch_metadata-miss");
+
+ /* Ratios */
+ arc_hits = (gauge_t) get_zfs_value(ksp, "hits");
+ arc_misses = (gauge_t) get_zfs_value(ksp, "misses");
+ l2_hits = (gauge_t) get_zfs_value(ksp, "l2_hits");
+ l2_misses = (gauge_t) get_zfs_value(ksp, "l2_misses");
+
+ za_submit_ratio ("arc", arc_hits, arc_misses);
+ za_submit_ratio ("L2", l2_hits, l2_misses);
+
+ /* I/O */
+ l2_io[0].derive = get_zfs_value(ksp, "l2_read_bytes");
+ l2_io[1].derive = get_zfs_value(ksp, "l2_write_bytes");
+
+ za_submit ("io_octets", "L2", l2_io, /* num values = */ 2);
+
+#if defined(KERNEL_LINUX)
+ if (llvalues != NULL)
+ {
+ free(llvalues);
+ }
+ if (ksp != NULL)
+ {
+ llist_destroy (ksp);
+ }
+#endif
+
+ return (0);
+} /* int za_read */
+
+static int za_init (void) /* {{{ */
+{
+#if !defined(__FreeBSD__) && !defined(KERNEL_LINUX) // Solaris
+ /* kstats chain already opened by update_kstat (using *kc), verify everything went fine. */
+ if (kc == NULL)
+ {
+ ERROR ("zfs_arc plugin: kstat chain control structure not available.");
+ return (-1);
+ }
+#endif
+
+ return (0);
+} /* }}} int za_init */
+
+void module_register (void)
+{
+ plugin_register_init ("zfs_arc", za_init);
+ plugin_register_read ("zfs_arc", za_read);
+} /* void module_register */
+
+/* vmi: set sw=8 noexpandtab fdm=marker : */