Index: files/patch-zfsarc
===================================================================
--- files/patch-zfsarc	(revision 0)
+++ files/patch-zfsarc	(working copy)
@@ -0,0 +1,131 @@
+diff --git configure.in configure.in
+index 1cfc2fc..f362459 100644
+--- configure.in
++++ configure.in
+@@ -71,6 +71,10 @@ case $host_os in
+ 	AC_DEFINE([KERNEL_AIX], 1, [True if program is to be compiled for a AIX kernel])
+ 	ac_system="AIX"
+ 	;;
++	*freebsd*)
++	AC_DEFINE([KERNEL_FREEBSD], 1, [True if program is to be compiled for a FreeBSD kernel])
++	ac_system="FreeBSD"
++	;;
+ 	*)
+ 	ac_system="unknown"
+ esac
+@@ -4557,6 +4561,12 @@ then
+         plugin_tcpconns="yes"
+ fi
+ 
++if test "x$ac_system" = "xFreeBSD"
++then
++        plugin_zfs_arc="yes"
++fi
++
++
+ if test "x$with_perfstat" = "xyes"
+ then
+ 	plugin_cpu="yes"
+diff --git src/Makefile.am src/Makefile.am
+index ab580d7..8900ecd 100644
+--- src/Makefile.am
++++ src/Makefile.am
+@@ -1315,7 +1315,6 @@ pkglib_LTLIBRARIES += zfs_arc.la
+ zfs_arc_la_SOURCES = zfs_arc.c
+ zfs_arc_la_CFLAGS = $(AM_CFLAGS)
+ zfs_arc_la_LDFLAGS = -module -avoid-version
+-zfs_arc_la_LIBADD = -lkstat
+ collectd_LDADD += "-dlopen" zfs_arc.la
+ collectd_DEPENDENCIES += zfs_arc.la
+ endif
+diff --git src/zfs_arc.c src/zfs_arc.c
+index e77569f..e5b894c 100644
+--- src/zfs_arc.c
++++ src/zfs_arc.c
+@@ -28,8 +28,40 @@
+ /*
+  * Global variables
+  */
++#if !defined(__FreeBSD__)
+ static kstat_t *ksp;
+ extern kstat_ctl_t *kc;
++#else
++#include <sys/types.h>
++#include <sys/sysctl.h>
++
++static void *ksp = NULL;
++const char zfs_arcstat[] = "kstat.zfs.misc.arcstats.";
++#if defined(get_kstat_value)
++#undef get_kstat_value
++#endif
++#if !defined(kstat_t)
++typedef void kstat_t;
++#endif
++
++static long long get_kstat_value(void * dummy __unused, const char *kstat_value)
++{
++	long long value;
++	size_t valuelen = sizeof(value);
++	int length, rv;
++	char *key;
++
++	length = asprintf(&key, "%s%s", zfs_arcstat, kstat_value);
++	if (length) {
++		rv = sysctlbyname(key, (void *)&value, &valuelen, NULL, (size_t)0);
++		free(key);
++		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)
+ {
+@@ -69,6 +101,7 @@ static int za_read_derive (kstat_t *ksp, const char *kstat_value,
+ 
+   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,
+@@ -86,6 +119,7 @@ static int za_read_gauge (kstat_t *ksp, const char *kstat_value,
+ 
+   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)
+@@ -108,12 +142,14 @@ static int za_read (void)
+ 	gauge_t  arc_hits, arc_misses, l2_hits, l2_misses;
+ 	value_t  l2_io[2];
+ 
++#if !defined(__FreeBSD__)
+ 	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");
+@@ -165,12 +201,14 @@ static int za_init (void) /* {{{ */
+ {
+ 	ksp = NULL;
+ 
++#if !defined(__FreeBSD__)
+ 	/* 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 */
Index: pkg-plist
===================================================================
--- pkg-plist	(revision 303393)
+++ pkg-plist	(working copy)
@@ -113,6 +113,8 @@
 libdata/pkgconfig/libcollectdclient.pc
 %%XMMS%%lib/collectd/xmms.la
 %%XMMS%%lib/collectd/xmms.so
+%%ZFSARC%%lib/collectd/zfs_arc.la
+%%ZFSARC%%lib/collectd/zfs_arc.so
 %%DATADIR%%/postgresql_default.conf
 %%DATADIR%%/types.db
 @dirrm lib/collectd
Index: Makefile
===================================================================
--- Makefile	(revision 303393)
+++ Makefile	(working copy)
@@ -48,7 +48,8 @@
 		TOKYOTYRANT	"Input: Tokyotyrant database"			Off \
 		XMMS		"Input: XMMS" 					Off \
 		RRDTOOL		"Output: RRDTool"				On  \
-		RRDCACHED	"Output: RRDTool Cached (require RRDTOOL)"	On
+		RRDCACHED	"Output: RRDTool Cached (require RRDTOOL)"	On  \
+		ZFSARC		"Input: ZFS ARC statistics"			On
 
 MAN1=		collectd.1 collectd-nagios.1 collectdmon.1 collectdctl.1
 MAN5=		collectd.conf.5 collectd-email.5 collectd-exec.5 \
@@ -127,7 +128,6 @@
 		--disable-vserver \
 		--disable-wireless \
 		--disable-write_http \
-		--disable-zfs_arc \
 		--without-perl-bindings \
 		--without-librabbitmq \
 		--disable-varnish \
@@ -394,6 +394,14 @@
 PLIST_SUB+=	XMMS="@comment "
 .endif
 
+.if defined(WITH_ZFSARC)
+CONFIGURE_ARGS+=--enable-zfs_arc
+PLIST_SUB+=	ZFSARC=""
+.else
+CONFIGURE_ARGS+=--disable-zfs_arc
+PLIST_SUB+=	ZFSARC="@comment "
+.endif
+
 AUTOTOOLSFILES=	aclocal.m4
 
 post-patch: