zfs

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"]