This ZFS plugin provides metrics from your ZFS filesystems. It supports ZFS on
Linux and FreeBSD. It gets ZFS stat from /proc/spl/kstat/zfs
on Linux and
from sysctl
and zpool
on 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
## If not specified, then default is:
# kstatMetrics = ["arcstats", "zfetchstats", "vdev_cache_stats"]
## By default, don't gather zpool stats
# poolMetrics = false
By default this plugin collects metrics about Arc, Zfetch, and
Vdev cache. All these metrics are either counters or measure sizes
in bytes. These metrics will be in the zfs
measurement with the field
names listed bellow.
If poolMetrics
is enabled then additional metrics will be gathered for
each pool.
- zfs With fields listed bellow.
- 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)
- 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)
- vdev_cache_stats_delegations
- vdev_cache_stats_hits
- vdev_cache_stats_misses
On Linux:
- zfs_pool
- nread (integer, )
- nwritten (integer, )
- reads (integer, )
- writes (integer, )
- wtime (integer, )
- wlentime (integer, )
- wupdate (integer, )
- rtime (integer, )
- rlentime (integer, )
- rupdate (integer, )
- wcnt (integer, )
- rcnt (integer, )
On FreeBSD:
- zfs_pool
- allocated (integer, bytes)
- capacity (integer, bytes)
- dedupratio (float, ratio)
- free (integer, bytes)
- size (integer, bytes)
- fragmentation (integer, percent)
-
ZFS stats (
zfs
) will have the following tag:- pools - A
::
concatenated list of all ZFS pools on the machine.
- pools - A
-
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)
$ ./telegraf -config telegraf.conf -input-filter zfs -test
* Plugin: zfs, Collection 1
> zfs_pool,health=ONLINE,pool=zroot allocated=1578590208i,capacity=2i,dedupratio=1,fragmentation=1i,free=64456531968i,size=66035122176i 1464473103625653908
> 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
A short description for some of the metrics.
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 whithout 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.
zfetchstats_hits
Counts the number of cache hits, to items which are in the cache because of the prefetcher.
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_hits
Hits to the vdev (device level) cache.
vdev_cache_stats_misses
Misses to the vdev (device level) cache.