--- title: Telegraf Documentation description: Telegraf plugin for collecting metrics from ZFS url: https://docs.influxdata.com/telegraf/v1/input-plugins/zfs/ estimated_tokens: 5851 product: Telegraf version: v1 --- - Telegraf v0.2.1+ # ZFS Input Plugin This plugin gathers metrics from [ZFS](https://en.wikipedia.org/wiki/ZFS) filesystems using `/proc/spl/kstat/zfs` on Linux and `sysctl`, `zfs` and `zpool` on FreeBSD. **Introduced in:** Telegraf v0.2.1 **Tags:** system **OS support:** freebsd, linux ## Global configuration options Plugins support additional global and plugin configuration settings for tasks such as modifying metrics, tags, and fields, creating aliases, and configuring plugin ordering. See [CONFIGURATION.md](/telegraf/v1/configuration/#plugins) for more details. ## Configuration ```toml # Read metrics of ZFS from arcstats, zfetchstats, vdev_cache_stats, pools and datasets # This plugin ONLY supports Linux & FreeBSD [[inputs.zfs]] ## ZFS kstat path. Ignored on FreeBSD ## If not specified, then default is: # kstatPath = "/proc/spl/kstat/zfs" ## By default, telegraf gather all zfs stats ## Override the stats list using the kstatMetrics array: ## For FreeBSD, the default is: # kstatMetrics = ["arcstats", "zfetchstats", "vdev_cache_stats"] ## For Linux, the default is: # kstatMetrics = ["abdstats", "arcstats", "dnodestats", "dbufcachestats", # "dmu_tx", "fm", "vdev_mirror_stats", "zfetchstats", "zil"] ## By default, don't gather zpool stats # poolMetrics = false ## By default, don't gather dataset stats # datasetMetrics = false ## Report fields as the type defined by ZFS (Linux only) ## This is disabled for backward compatibility but is STRONGLY RECOMMENDED ## to be enabled to avoid overflows. This requires UINT support on the output ## for most fields. ## useNativeTypes = false ``` OpenZFS on Linux reports the type of fields especially for the dataset metrics. By default this plugin will ignore the provided type and will report metrics as signed 64-bit integers. It is **highly recommended** to use the reported type by setting `useNativeTypes` to `true` for avoiding overflows of field values as most fields are reported as **unsigned** 64-bit integers. Additionally, you must make sure your output supports reporting unsigned values! Changing the setting for `useNativeTypes` will generate metrics with conflicting field types so you need to either migrate existing data or clear your database for e.g. InfluxDB outputs! ## Metrics By default this plugin collects metrics about ZFS internals pool and dataset. These metrics are either counters or measure sizes in bytes. These metrics will be in the `zfs` measurement with the field names listed below. If `poolMetrics` is enabled then additional metrics will be gathered for each pool. If `datasetMetrics` is enabled then additional metrics will be gathered for each dataset. - zfs With fields listed below. ### ARC Stats (FreeBSD and Linux) - arcstats\_allocated (FreeBSD only) - arcstats\_anon\_evict\_data (Linux only) - arcstats\_anon\_evict\_metadata (Linux only) - arcstats\_anon\_evictable\_data (FreeBSD only) - arcstats\_anon\_evictable\_metadata (FreeBSD only) - arcstats\_anon\_size - arcstats\_arc\_loaned\_bytes (Linux only) - arcstats\_arc\_meta\_limit - arcstats\_arc\_meta\_max - arcstats\_arc\_meta\_min (FreeBSD only) - arcstats\_arc\_meta\_used - arcstats\_arc\_no\_grow (Linux only) - arcstats\_arc\_prune (Linux only) - arcstats\_arc\_tempreserve (Linux only) - arcstats\_c - arcstats\_c\_max - arcstats\_c\_min - arcstats\_data\_size - arcstats\_deleted - arcstats\_demand\_data\_hits - arcstats\_demand\_data\_misses - arcstats\_demand\_hit\_predictive\_prefetch (FreeBSD only) - arcstats\_demand\_metadata\_hits - arcstats\_demand\_metadata\_misses - arcstats\_duplicate\_buffers - arcstats\_duplicate\_buffers\_size - arcstats\_duplicate\_reads - arcstats\_evict\_l2\_cached - arcstats\_evict\_l2\_eligible - arcstats\_evict\_l2\_ineligible - arcstats\_evict\_l2\_skip (FreeBSD only) - arcstats\_evict\_not\_enough (FreeBSD only) - arcstats\_evict\_skip - arcstats\_hash\_chain\_max - arcstats\_hash\_chains - arcstats\_hash\_collisions - arcstats\_hash\_elements - arcstats\_hash\_elements\_max - arcstats\_hdr\_size - arcstats\_hits - arcstats\_l2\_abort\_lowmem - arcstats\_l2\_asize - arcstats\_l2\_cdata\_free\_on\_write - arcstats\_l2\_cksum\_bad - arcstats\_l2\_compress\_failures - arcstats\_l2\_compress\_successes - arcstats\_l2\_compress\_zeros - arcstats\_l2\_evict\_l1cached (FreeBSD only) - arcstats\_l2\_evict\_lock\_retry - arcstats\_l2\_evict\_reading - arcstats\_l2\_feeds - arcstats\_l2\_free\_on\_write - arcstats\_l2\_hdr\_size - arcstats\_l2\_hits - arcstats\_l2\_io\_error - arcstats\_l2\_misses - arcstats\_l2\_read\_bytes - arcstats\_l2\_rw\_clash - arcstats\_l2\_size - arcstats\_l2\_write\_buffer\_bytes\_scanned (FreeBSD only) - arcstats\_l2\_write\_buffer\_iter (FreeBSD only) - arcstats\_l2\_write\_buffer\_list\_iter (FreeBSD only) - arcstats\_l2\_write\_buffer\_list\_null\_iter (FreeBSD only) - arcstats\_l2\_write\_bytes - arcstats\_l2\_write\_full (FreeBSD only) - arcstats\_l2\_write\_in\_l2 (FreeBSD only) - arcstats\_l2\_write\_io\_in\_progress (FreeBSD only) - arcstats\_l2\_write\_not\_cacheable (FreeBSD only) - arcstats\_l2\_write\_passed\_headroom (FreeBSD only) - arcstats\_l2\_write\_pios (FreeBSD only) - arcstats\_l2\_write\_spa\_mismatch (FreeBSD only) - arcstats\_l2\_write\_trylock\_fail (FreeBSD only) - arcstats\_l2\_writes\_done - arcstats\_l2\_writes\_error - arcstats\_l2\_writes\_hdr\_miss (Linux only) - arcstats\_l2\_writes\_lock\_retry (FreeBSD only) - arcstats\_l2\_writes\_sent - arcstats\_memory\_direct\_count (Linux only) - arcstats\_memory\_indirect\_count (Linux only) - arcstats\_memory\_throttle\_count - arcstats\_meta\_size (Linux only) - arcstats\_mfu\_evict\_data (Linux only) - arcstats\_mfu\_evict\_metadata (Linux only) - arcstats\_mfu\_ghost\_evict\_data (Linux only) - arcstats\_mfu\_ghost\_evict\_metadata (Linux only) - arcstats\_metadata\_size (FreeBSD only) - arcstats\_mfu\_evictable\_data (FreeBSD only) - arcstats\_mfu\_evictable\_metadata (FreeBSD only) - arcstats\_mfu\_ghost\_evictable\_data (FreeBSD only) - arcstats\_mfu\_ghost\_evictable\_metadata (FreeBSD only) - arcstats\_mfu\_ghost\_hits - arcstats\_mfu\_ghost\_size - arcstats\_mfu\_hits - arcstats\_mfu\_size - arcstats\_misses - arcstats\_mru\_evict\_data (Linux only) - arcstats\_mru\_evict\_metadata (Linux only) - arcstats\_mru\_ghost\_evict\_data (Linux only) - arcstats\_mru\_ghost\_evict\_metadata (Linux only) - arcstats\_mru\_evictable\_data (FreeBSD only) - arcstats\_mru\_evictable\_metadata (FreeBSD only) - arcstats\_mru\_ghost\_evictable\_data (FreeBSD only) - arcstats\_mru\_ghost\_evictable\_metadata (FreeBSD only) - arcstats\_mru\_ghost\_hits - arcstats\_mru\_ghost\_size - arcstats\_mru\_hits - arcstats\_mru\_size - arcstats\_mutex\_miss - arcstats\_other\_size - arcstats\_p - arcstats\_prefetch\_data\_hits - arcstats\_prefetch\_data\_misses - arcstats\_prefetch\_metadata\_hits - arcstats\_prefetch\_metadata\_misses - arcstats\_recycle\_miss (Linux only) - arcstats\_size - arcstats\_sync\_wait\_for\_async (FreeBSD only) with the following meaning - `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` Amount of cache hits for demand metadata, this matters (is good) for getting filesystem data (ls,find,…) - `arcstats_demand_metadata_misses` Amount 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 something, but it was already 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 frequently used cache” we move this to the beginning 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 without an l2 device. - The zfs property secondary cache. - `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 something is in the l2) the l2 cache. ### Zfetch Stats (FreeBSD and Linux) - zfetchstats\_bogus\_streams (Linux only) - zfetchstats\_colinear\_hits (Linux only) - zfetchstats\_colinear\_misses (Linux only) - zfetchstats\_hits - zfetchstats\_max\_streams (FreeBSD only) - zfetchstats\_misses - zfetchstats\_reclaim\_failures (Linux only) - zfetchstats\_reclaim\_successes (Linux only) - zfetchstats\_streams\_noresets (Linux only) - zfetchstats\_streams\_resets (Linux only) - zfetchstats\_stride\_hits (Linux only) - zfetchstats\_stride\_misses (Linux only) with the following meaning: - `zfetchstats_hits` Counts the number of cache hits, to items which are in the cache because of the prefetcher. - `zfetchstats_misses` Counts the number of prefetch cache misses. - `zfetchstats_colinear_hits` Counts the number of cache hits, to items which are in the cache because of the prefetcher (prefetched linear reads) - `zfetchstats_stride_hits` Counts the number of cache hits, to items which are in the cache because of the prefetcher (prefetched stride reads) ### Vdev Cache Stats (FreeBSD) The vdev cache is deprecated in some ZFS implementations. - vdev\_cache\_stats\_delegations - vdev\_cache\_stats\_hits - vdev\_cache\_stats\_misses with the following meaning: - `vdev_cache_stats_hits` Hits to the vdev (device level) cache. - `vdev_cache_stats_misses` Misses to the vdev (device level) cache. ### Pool Metrics (optional) On Linux (reference: kstat accumulated time and queue length statistics): - zfs\_pool - nread (integer, bytes) - nwritten (integer, bytes) - reads (integer, count) - writes (integer, count) - wtime (integer, nanoseconds) - wlentime (integer, queuelength \* nanoseconds) - wupdate (integer, timestamp) - rtime (integer, nanoseconds) - rlentime (integer, queuelength \* nanoseconds) - rupdate (integer, timestamp) - wcnt (integer, count) - rcnt (integer, count) For ZFS >= 2.1.x the format has changed significantly: - zfs\_pool - writes (integer, count) - nwritten (integer, bytes) - reads (integer, count) - nread (integer, bytes) - nunlinks (integer, count) - nunlinked (integer, count) For ZFS >= 2.2.x the following additional fields are available: - additional fields for ZFS > 2.2.x - zil\_commit\_count (integer, count) - zil\_commit\_writer\_count (integer, count) - zil\_itx\_count (integer, count) - zil\_itx\_indirect\_count (integer, count) - zil\_itx\_indirect\_bytes (integer, bytes) - zil\_itx\_copied\_count (integer, count) - zil\_itx\_copied\_bytes (integer, bytes) - zil\_itx\_needcopy\_count (integer, count) - zil\_itx\_needcopy\_bytes (integer, bytes) - zil\_itx\_metaslab\_normal\_count (integer, count) - zil\_itx\_metaslab\_normal\_bytes (integer, bytes) - zil\_itx\_metaslab\_normal\_write (integer, bytes) - zil\_itx\_metaslab\_normal\_alloc (integer, bytes) - zil\_itx\_metaslab\_slog\_count (integer, count) - zil\_itx\_metaslab\_slog\_bytes (integer, bytes) - zil\_itx\_metaslab\_slog\_write (integer, bytes) - zil\_itx\_metaslab\_slog\_alloc (integer, bytes) On FreeBSD: - zfs\_pool - allocated (integer, bytes) - capacity (integer, bytes) - dedupratio (float, ratio) - free (integer, bytes) - size (integer, bytes) - fragmentation (integer, percent) The `zil` measurements in `kstatMetrics` are system-wide while the once in `poolMetrics` are pool-wide - `zil_commit_count` counts when ZFS transactions are committed to a ZIL ### Dataset Metrics (optional, only on FreeBSD) - zfs\_dataset - avail (integer, bytes) - used (integer, bytes) - usedsnap (integer, bytes) - usedds (integer, bytes) ### ABD Stats (Linux Only) ABD is a linear/scatter dual typed buffer for ARC - `abdstats_linear_cnt` number of linear ABDs which are currently allocated - `abdstats_linear_data_size` amount of data stored in all linear ABDs - `abdstats_scatter_cnt` number of scatter ABDs which are currently allocated - `abdstats_scatter_data_size` amount of data stored in all scatter ABDs ### DMU Stats (Linux Only) - `dmu_tx_dirty_throttle` counts when writes are throttled due to the amount of dirty data growing too large - `dmu_tx_memory_reclaim` counts when memory is low and throttling activity - `dmu_tx_memory_reserve` counts when memory footprint of the txg exceeds the ARC size ### Fault Management Ereport errors (Linux Only) - `fm_erpt-dropped` counts when an error report cannot be created (eg available memory is too low) ### Tags - ZFS stats (`zfs`) will have the following tag: - pools - A `::` concatenated list of all ZFS pools on the machine. - datasets - A `::` concatenated list of all ZFS datasets on the machine. - Pool metrics (`zfs_pool`) will have the following tag: - pool - with the name of the pool which the metrics are for. - health - the health status of the pool. (FreeBSD only) - dataset - ZFS >= 2.1.x only. (Linux only) - Dataset metrics (`zfs_dataset`) will have the following tag: - dataset - with the name of the dataset which the metrics are for. ## Example Output ```text zfs_pool,health=ONLINE,pool=zroot allocated=1578590208i,capacity=2i,dedupratio=1,fragmentation=1i,free=64456531968i,size=66035122176i 1464473103625653908 zfs_dataset,dataset=zata avail=10741741326336,used=8564135526400,usedsnap=0,usedds=90112 zfs,pools=zroot arcstats_allocated=4167764i,arcstats_anon_evictable_data=0i,arcstats_anon_evictable_metadata=0i,arcstats_anon_size=16896i,arcstats_arc_meta_limit=10485760i,arcstats_arc_meta_max=115269568i,arcstats_arc_meta_min=8388608i,arcstats_arc_meta_used=51977456i,arcstats_c=16777216i,arcstats_c_max=41943040i,arcstats_c_min=16777216i,arcstats_data_size=0i,arcstats_deleted=1699340i,arcstats_demand_data_hits=14836131i,arcstats_demand_data_misses=2842945i,arcstats_demand_hit_predictive_prefetch=0i,arcstats_demand_metadata_hits=1655006i,arcstats_demand_metadata_misses=830074i,arcstats_duplicate_buffers=0i,arcstats_duplicate_buffers_size=0i,arcstats_duplicate_reads=123i,arcstats_evict_l2_cached=0i,arcstats_evict_l2_eligible=332172623872i,arcstats_evict_l2_ineligible=6168576i,arcstats_evict_l2_skip=0i,arcstats_evict_not_enough=12189444i,arcstats_evict_skip=195190764i,arcstats_hash_chain_max=2i,arcstats_hash_chains=10i,arcstats_hash_collisions=43134i,arcstats_hash_elements=2268i,arcstats_hash_elements_max=6136i,arcstats_hdr_size=565632i,arcstats_hits=16515778i,arcstats_l2_abort_lowmem=0i,arcstats_l2_asize=0i,arcstats_l2_cdata_free_on_write=0i,arcstats_l2_cksum_bad=0i,arcstats_l2_compress_failures=0i,arcstats_l2_compress_successes=0i,arcstats_l2_compress_zeros=0i,arcstats_l2_evict_l1cached=0i,arcstats_l2_evict_lock_retry=0i,arcstats_l2_evict_reading=0i,arcstats_l2_feeds=0i,arcstats_l2_free_on_write=0i,arcstats_l2_hdr_size=0i,arcstats_l2_hits=0i,arcstats_l2_io_error=0i,arcstats_l2_misses=0i,arcstats_l2_read_bytes=0i,arcstats_l2_rw_clash=0i,arcstats_l2_size=0i,arcstats_l2_write_buffer_bytes_scanned=0i,arcstats_l2_write_buffer_iter=0i,arcstats_l2_write_buffer_list_iter=0i,arcstats_l2_write_buffer_list_null_iter=0i,arcstats_l2_write_bytes=0i,arcstats_l2_write_full=0i,arcstats_l2_write_in_l2=0i,arcstats_l2_write_io_in_progress=0i,arcstats_l2_write_not_cacheable=380i,arcstats_l2_write_passed_headroom=0i,arcstats_l2_write_pios=0i,arcstats_l2_write_spa_mismatch=0i,arcstats_l2_write_trylock_fail=0i,arcstats_l2_writes_done=0i,arcstats_l2_writes_error=0i,arcstats_l2_writes_lock_retry=0i,arcstats_l2_writes_sent=0i,arcstats_memory_throttle_count=0i,arcstats_metadata_size=17014784i,arcstats_mfu_evictable_data=0i,arcstats_mfu_evictable_metadata=16384i,arcstats_mfu_ghost_evictable_data=5723648i,arcstats_mfu_ghost_evictable_metadata=10709504i,arcstats_mfu_ghost_hits=1315619i,arcstats_mfu_ghost_size=16433152i,arcstats_mfu_hits=7646611i,arcstats_mfu_size=305152i,arcstats_misses=3676993i,arcstats_mru_evictable_data=0i,arcstats_mru_evictable_metadata=0i,arcstats_mru_ghost_evictable_data=0i,arcstats_mru_ghost_evictable_metadata=80896i,arcstats_mru_ghost_hits=324250i,arcstats_mru_ghost_size=80896i,arcstats_mru_hits=8844526i,arcstats_mru_size=16693248i,arcstats_mutex_miss=354023i,arcstats_other_size=34397040i,arcstats_p=4172800i,arcstats_prefetch_data_hits=0i,arcstats_prefetch_data_misses=0i,arcstats_prefetch_metadata_hits=24641i,arcstats_prefetch_metadata_misses=3974i,arcstats_size=51977456i,arcstats_sync_wait_for_async=0i,vdev_cache_stats_delegations=779i,vdev_cache_stats_hits=323123i,vdev_cache_stats_misses=59929i,zfetchstats_hits=0i,zfetchstats_max_streams=0i,zfetchstats_misses=0i 1464473103634124908 ``` #### Related - [Configure plugins](/telegraf/v1/configure_plugins/) - [ZFS Plugin Source](https://github.com/influxdata/telegraf/tree/v1.38.4/plugins/inputs/zfs/README.md)