Cache Container Metrics (Memcached)

The following table describes the metrics that are required for monitoring the health of the Memcached services.
Note:
  • Data field is the name of the metric in the captured data.
  • Slab stats are prefixed by sn_ where n is the slab number.
  • For more information on memcached monitoring, see https://github.com/memcached/memcached/wiki/ServerMaint.
Memcached Per pool metrics 
{
   "time":1554455492,
   "message":{
      "tag":"tml-cache.cache-set-0-0.metrics.stats.memcached.11211",
      "ingestion_time":"2019-04-05T09:11:32+00:00",
      "pool_name":"mapis",
      "pool":11211,
      "pid":343,
      "uptime":6912,
      "time":1554455487,
      "version":"1.5.7",
      "libevent":"2.0.21-stable",
      "pointer_size":64,
      "rusage_user":"0.714312",
      "rusage_system":"0.878758",
      "max_connections":10240,
      "curr_connections":5,
      "total_connections":462,
      "rejected_connections":0,
      "connection_structures":8,
      "reserved_fds":20,
      "cmd_get":23,
      "cmd_set":2071,
      "cmd_flush":0,
      "cmd_touch":0,
      "get_hits":22,
      "get_misses":1,
      "get_expired":0,
      "get_flushed":0,
      "delete_misses":0,
      "delete_hits":0,
      "incr_misses":0,
      "incr_hits":0,
      "decr_misses":0,
      "decr_hits":0,
      "cas_misses":0,
      "cas_hits":0,
      "cas_badval":0,
      "touch_hits":0,
      "touch_misses":0,
      "auth_cmds":0,
      "auth_errors":0,
      "bytes_read":3015690,
      "bytes_written":843044,
      "limit_maxbytes":402653184,
      "accepting_conns":1,
      "listen_disabled_num":0,
      "time_in_listen_disabled_us":0,
      "threads":4,
      "conn_yields":0,
      "hash_power_level":16,
      "hash_bytes":524288,
      "hash_is_expanding":0,
      "slab_reassign_rescues":0,
      "slab_reassign_chunk_rescues":0,
      "slab_reassign_evictions_nomem":0,
      "slab_reassign_inline_reclaim":0,
      "slab_reassign_busy_items":0,
      "slab_reassign_busy_deletes":0,
      "slab_reassign_running":0,
      "slabs_moved":0,
      "lru_crawler_running":0,
      "lru_crawler_starts":3825,
      "lru_maintainer_juggles":34718,
      "malloc_fails":0,
      "log_worker_dropped":0,
      "log_worker_written":0,
      "log_watcher_skipped":0,
      "log_watcher_sent":0,
      "bytes":1545247,
      "curr_items":1015,
      "total_items":2071,
      "slab_global_page_pool":0,
      "expired_unfetched":0,
      "evicted_unfetched":0,
      "evicted_active":0,
      "evictions":0,
      "reclaimed":0,
      "crawler_reclaimed":0,
      "crawler_items_checked":12180,
      "lrutail_reflocked":0,
      "moves_to_cold":2071,
      "moves_to_warm":1,
      "moves_within_lru":20,
      "direct_reclaims":0,
      "lru_bumps_dropped":0
   }
}
Memcached Per pool per slab metrics 
{
   "time":1554455492,
   "message":{
      "tag":"tml-cache.cache-set-0-0.metrics.stats.memcached.11211",
      "ingestion_time":"2019-04-05T09:11:32+00:00",
      "pool_name":"mapis",
      "pool":11211,
      "slab_class":1,
      "chunk_size":0,
      "chunk_per_page":0,
      "total_pages":0,
      "total_chunks":10922,
      "used_chunks":3,
      "free_chunks":10919,
      "free_chunks_end":0,
      "mem_requested":271,
      "get_hits":22,
      "cmd_set":47,
      "delete_hits":0,
      "incr_hits":0,
      "decr_hits":0,
      "cas_hits":0,
      "cas_badval":0,
      "touch_hits":0
   }
}
Name Data Field Unit Data Type Notes Details
Pool Name pool_name N/A String Possible values counter, services, mapis, httpclientsecurity, packager, content The pool name maps to a Pool
pool pool N/A Number The port number on which the pool is listening for Memcached function calls Possible values 11211, 11212, 11213, 11214, 11215,11216 11211 = mapis, 11212 = counter, 11213 = content, 11214 = services, 11215 = packages, 11216 = httpsclientsecurity
Particular slab slab_class N/A Number For each Memcache, there could be multiple slabs, slab_class denotes which slab it is.
Process id pid N/A Number Process id of memcached services- there will be one PID per memcached pool
Up time uptime N/A Number Time since start of process - denotes how long the process has been active.
Maximum connections max_connections N/A Number Max connections allowed for this pool
Total connections total_connections N/A Number Total number of successful connections since start
Current client connections curr_connections N/A Number Number of Memcached clients connected at this point
Total GETs cmd_get N/A Number Number of times a Get request was made- includes both successful and unsuccessful
Total SETs cmd_set N/A Number Number of times a Set request was made - includes both successful and unsuccessful
Total Get hits get_hits N/A Number Number of successful GET requets
Total GET misses get_misses N/A Number Number of failed "get" requests because nothing was cached for requested key.
get hits get_hits N/A Number Number of hits for the slab - this should be > sn_cmd_set
chunk size chunk_size Bytes Number Size of item chunks.
Number of chunks in a page chunks_per_page Bytes Number Total number of chunks in a Page - This will compute as chunk_size*total_chunks = 1MB approximately.