add ZFS plugin

README.md

@@ -190,6 +190,7 @@ Telegraf currently has support for collecting metrics from:
 * rabbitmq
 * redis
 * rethinkdb
+* zfs
 * zookeeper
 * system
     * cpu

plugins/all/all.go

@@ -28,5 +28,6 @@ import (
 	_ "github.com/influxdb/telegraf/plugins/rethinkdb"
 	_ "github.com/influxdb/telegraf/plugins/statsd"
 	_ "github.com/influxdb/telegraf/plugins/system"
+	_ "github.com/influxdb/telegraf/plugins/zfs"
 	_ "github.com/influxdb/telegraf/plugins/zookeeper"
 )

plugins/zfs/README.md

@@ -0,0 +1,227 @@
+# Telegraf plugin: zfs
+
+Get ZFS stat from /proc/spl/kstat/zfs
+
+# Measurements
+
+Meta:
+
+- tags: `pools=POOL1::POOL2`
+
+Measurement names:
+
+- arcstats_hits
+- arcstats_misses
+- arcstats_demand_data_hits
+- arcstats_demand_data_misses
+- arcstats_demand_metadata_hits
+- arcstats_demand_metadata_misses
+- arcstats_prefetch_data_hits
+- arcstats_prefetch_data_misses
+- arcstats_prefetch_metadata_hits
+- arcstats_prefetch_metadata_misses
+- arcstats_mru_hits
+- arcstats_mru_ghost_hits
+- arcstats_mfu_hits
+- arcstats_mfu_ghost_hits
+- arcstats_deleted
+- arcstats_recycle_miss
+- arcstats_mutex_miss
+- arcstats_evict_skip
+- arcstats_evict_l2_cached
+- arcstats_evict_l2_eligible
+- arcstats_evict_l2_ineligible
+- arcstats_hash_elements
+- arcstats_hash_elements_max
+- arcstats_hash_collisions
+- arcstats_hash_chains
+- arcstats_hash_chain_max
+- arcstats_p
+- arcstats_c
+- arcstats_c_min
+- arcstats_c_max
+- arcstats_size
+- arcstats_hdr_size
+- arcstats_data_size
+- arcstats_meta_size
+- arcstats_other_size
+- arcstats_anon_size
+- arcstats_anon_evict_data
+- arcstats_anon_evict_metadata
+- arcstats_mru_size
+- arcstats_mru_evict_data
+- arcstats_mru_evict_metadata
+- arcstats_mru_ghost_size
+- arcstats_mru_ghost_evict_data
+- arcstats_mru_ghost_evict_metadata
+- arcstats_mfu_size
+- arcstats_mfu_evict_data
+- arcstats_mfu_evict_metadata
+- arcstats_mfu_ghost_size
+- arcstats_mfu_ghost_evict_data
+- arcstats_mfu_ghost_evict_metadata
+- arcstats_l2_hits
+- arcstats_l2_misses
+- arcstats_l2_feeds
+- arcstats_l2_rw_clash
+- arcstats_l2_read_bytes
+- arcstats_l2_write_bytes
+- arcstats_l2_writes_sent
+- arcstats_l2_writes_done
+- arcstats_l2_writes_error
+- arcstats_l2_writes_hdr_miss
+- arcstats_l2_evict_lock_retry
+- arcstats_l2_evict_reading
+- arcstats_l2_free_on_write
+- arcstats_l2_cdata_free_on_write
+- arcstats_l2_abort_lowmem
+- arcstats_l2_cksum_bad
+- arcstats_l2_io_error
+- arcstats_l2_size
+- arcstats_l2_asize
+- arcstats_l2_hdr_size
+- arcstats_l2_compress_successes
+- arcstats_l2_compress_zeros
+- arcstats_l2_compress_failures
+- arcstats_memory_throttle_count
+- arcstats_duplicate_buffers
+- arcstats_duplicate_buffers_size
+- arcstats_duplicate_reads
+- arcstats_memory_direct_count
+- arcstats_memory_indirect_count
+- arcstats_arc_no_grow
+- arcstats_arc_tempreserve
+- arcstats_arc_loaned_bytes
+- arcstats_arc_prune
+- arcstats_arc_meta_used
+- arcstats_arc_meta_limit
+- arcstats_arc_meta_max
+- zfetchstats_hits
+- zfetchstats_misses
+- zfetchstats_colinear_hits
+- zfetchstats_colinear_misses
+- zfetchstats_stride_hits
+- zfetchstats_stride_misses
+- zfetchstats_reclaim_successes
+- zfetchstats_reclaim_failures
+- zfetchstats_streams_resets
+- zfetchstats_streams_noresets
+- zfetchstats_bogus_streams
+- vdev_cache_stats_delegations
+- vdev_cache_stats_hits
+- vdev_cache_stats_misses
+
+### Description
+
+```
+arcstats_hits
+  Total amount of cache hits in the arc.
+
+arcstats_misses
+  Total amount of cache misses in the arc.
+
+arcstats_demand_data_hits
+  Amount of cache hits for demand data, this is what matters (is good) for your application/share.
+
+arcstats_demand_data_misses
+  Amount of cache misses for demand data, this is what matters (is bad) for your application/share.
+
+arcstats_demand_metadata_hits
+  Ammount of cache hits for demand metadata, this matters (is good) for getting filesystem data (ls,find,…)
+
+arcstats_demand_metadata_misses
+  Ammount of cache misses for demand metadata, this matters (is bad) for getting filesystem data (ls,find,…)
+
+arcstats_prefetch_data_hits
+  The zfs prefetcher tried to prefetch somethin, but it was allready cached (boring)
+
+arcstats_prefetch_data_misses
+  The zfs prefetcher prefetched something which was not in the cache (good job, could become a demand hit in the future)
+
+arcstats_prefetch_metadata_hits
+  Same as above, but for metadata
+
+arcstats_prefetch_metadata_misses
+  Same as above, but for metadata
+
+arcstats_mru_hits
+  Cache hit in the “most recently used cache”, we move this to the mfu cache.
+
+arcstats_mru_ghost_hits
+  Cache hit in the “most recently used ghost list” we had this item in the cache, but evicted it, maybe we should increase the mru cache size.
+
+arcstats_mfu_hits
+  Cache hit in the “most freqently used cache” we move this to the begining of the mfu cache.
+
+arcstats_mfu_ghost_hits
+  Cache hit in the “most frequently used ghost list” we had this item in the cache, but evicted it, maybe we should increase the mfu cache size.
+
+arcstats_allocated
+  New data is written to the cache.
+
+arcstats_deleted
+  Old data is evicted (deleted) from the cache.
+
+arcstats_evict_l2_cached
+  We evicted something from the arc, but its still cached in the l2 if we need it.
+
+arcstats_evict_l2_eligible
+  We evicted something from the arc, and it’s not in the l2 this is sad. (maybe we hadn’t had enough time to store it there)
+
+arcstats_evict_l2_ineligible
+  We evicted something which cannot be stored in the l2.
+  Reasons could be:
+  We have multiple pools, we evicted something from a pool whithot an l2 device.
+  The zfs property secondarycache.
+
+arcstats_c
+  Arc target size, this is the size the system thinks the arc should have.
+
+arcstats_size
+  Total size of the arc.
+
+arcstats_l2_hits
+  Hits to the L2 cache. (It was not in the arc, but in the l2 cache)
+
+arcstats_l2_misses
+  Miss to the L2 cache. (It was not in the arc, and not in the l2 cache)
+
+arcstats_l2_size
+  Size of the l2 cache.
+
+arcstats_l2_hdr_size
+  Size of the metadata in the arc (ram) used to manage (lookup if someting is in the l2) the l2 cache.
+
+
+
+zfetchstats_hits
+  Counts the number of cache hits, to items wich are in the cache because of the prefetcher.
+
+zfetchstats_colinear_hits
+  Counts the number of cache hits, to items wich are in the cache because of the prefetcher (prefetched linear reads)
+
+zfetchstats_stride_hits
+  Counts the number of cache hits, to items wich are in the cache because of the prefetcher (prefetched stride reads)
+
+
+
+vdev_cache_stats_hits
+  Hits to the vdev (device level) cache.
+
+vdev_cache_stats_misses
+  Misses to the vdev (device level) cache.
+```
+
+# Default config
+
+```
+[zfs]
+  # ZFS kstat path
+  # If not specified, then default is:
+  # kstatPath = "/proc/spl/kstat/zfs"
+  #
+  # By default, telegraf gather all zfs stats
+  # If not specified, then default is:
+  # kstatMetrics = ["arcstats", "zfetchstats", "vdev_cache_stats"]
+```
+

plugins/zfs/zfs.go

@@ -0,0 +1,88 @@
+package zfs
+
+import (
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"github.com/influxdb/telegraf/plugins"
+	"github.com/shirou/gopsutil/common"
+)
+
+type Zfs struct {
+	KstatPath    string
+	KstatMetrics []string
+}
+
+var sampleConfig = `
+  # ZFS kstat path
+  # If not specified, then default is:
+  # kstatPath = "/proc/spl/kstat/zfs"
+  #
+  # By default, telegraf gather all zfs stats
+  # If not specified, then default is:
+  # kstatMetrics = ["arcstats", "zfetchstats", "vdev_cache_stats"]
+`
+
+func (z *Zfs) SampleConfig() string {
+	return sampleConfig
+}
+
+func (z *Zfs) Description() string {
+	return "Read metrics of ZFS from arcstats, zfetchstats and vdev_cache_stats"
+}
+
+func getTags(kstatPath string) map[string]string {
+	var pools string
+	poolsDirs, _ := filepath.Glob(kstatPath + "/*/io")
+	for _, poolDir := range poolsDirs {
+		poolDirSplit := strings.Split(poolDir, "/")
+		pool := poolDirSplit[len(poolDirSplit)-2]
+		if len(pools) != 0 {
+			pools += "::"
+		}
+		pools += pool
+	}
+	return map[string]string{"pools": pools}
+}
+
+func (z *Zfs) Gather(acc plugins.Accumulator) error {
+	kstatMetrics := z.KstatMetrics
+	if len(kstatMetrics) == 0 {
+		kstatMetrics = []string{"arcstats", "zfetchstats", "vdev_cache_stats"}
+	}
+
+	kstatPath := z.KstatPath
+	if len(kstatPath) == 0 {
+		kstatPath = "/proc/spl/kstat/zfs"
+	}
+
+	tags := getTags(kstatPath)
+
+	for _, metric := range kstatMetrics {
+		lines, err := common.ReadLines(kstatPath + "/" + metric)
+		if err != nil {
+			return err
+		}
+		for i, line := range lines {
+			if i == 0 || i == 1 {
+				continue
+			}
+			if len(line) < 1 {
+				continue
+			}
+			rawData := strings.Split(line, " ")
+			key := metric + "_" + rawData[0]
+			rawValue := rawData[len(rawData)-1]
+			value, _ := strconv.ParseInt(rawValue, 10, 64)
+			acc.Add(key, value, tags)
+		}
+	}
+	return nil
+}
+
+func init() {
+	plugins.Add("zfs", func() plugins.Plugin {
+		return &Zfs{}
+	})
+}