This plugin has the ability to gather the following metrics:
| Namespace | Description |
|---|---|
| /raintank/memcache/general/pid | Process id of this server process |
| /raintank/memcache/general/uptime | Number of secs since the server started |
| /raintank/memcache/general/time | current UNIX time according to the server |
| /raintank/memcache/general/version | Version string of this server |
| /raintank/memcache/general/pointer_size | Default size of pointers on the host OS (generally 32 or 64) |
| /raintank/memcache/general/rusage_user | Accumulated user time for this process (seconds:microseconds) |
| /raintank/memcache/general/rusage_system | Accumulated system time for this process (seconds:microseconds) |
| /raintank/memcache/general/curr_items | Current number of items stored |
| /raintank/memcache/general/total_items | Total number of items stored since the server started |
| /raintank/memcache/general/bytes | Current number of bytes used to store items |
| /raintank/memcache/general/curr_connections | Number of open connections |
| /raintank/memcache/general/total_connections | Total number of connections opened since the server started running |
| /raintank/memcache/general/rejected_connections | Conns rejected in maxconns_fast mode |
| /raintank/memcache/general/connection_structures | Number of connection structures allocated by the server |
| /raintank/memcache/general/reserved_fds | Number of misc fds used internally |
| /raintank/memcache/general/cmd_get | Cumulative number of retrieval reqs |
| /raintank/memcache/general/cmd_set | Cumulative number of storage reqs |
| /raintank/memcache/general/cmd_flush | Cumulative number of flush reqs |
| /raintank/memcache/general/cmd_touch | Cumulative number of touch reqs |
| /raintank/memcache/general/get_hits | Number of keys that have been requested and found present |
| /raintank/memcache/general/get_misses | Number of items that have been requested and not found |
| /raintank/memcache/general/get_expired | Number of items that have been requested but had already expired. |
| /raintank/memcache/general/delete_misses | Number of deletions reqs for missing keys |
| /raintank/memcache/general/delete_hits | Number of deletion reqs resulting in an item being removed. |
| /raintank/memcache/general/incr_misses | Number of incr reqs against missing keys. |
| /raintank/memcache/general/incr_hits | Number of successful incr reqs. |
| /raintank/memcache/general/decr_misses | Number of decr reqs against missing keys. |
| /raintank/memcache/general/decr_hits | Number of successful decr reqs. |
| /raintank/memcache/general/cas_misses | Number of CAS reqs against missing keys. |
| /raintank/memcache/general/cas_hits | Number of successful CAS reqs. |
| /raintank/memcache/general/cas_badval | Number of CAS reqs for which a key was found, but the CAS value did not match. |
| /raintank/memcache/general/touch_hits | Numer of keys that have been touched with a new expiration time |
| /raintank/memcache/general/touch_misses | Numer of items that have been touched and not found |
| /raintank/memcache/general/auth_cmds | Number of authentication commands handled, success or failure. |
| /raintank/memcache/general/auth_errors | Number of failed authentications. |
| /raintank/memcache/general/evictions | Number of valid items removed from cache to free memory for new items |
| /raintank/memcache/general/reclaimed | Number of times an entry was stored using memory from an expired entry |
| /raintank/memcache/general/bytes_read | Total number of bytes read by this server from network |
| /raintank/memcache/general/bytes_written | Total number of bytes sent by this server to network |
| /raintank/memcache/general/limit_maxbytes | Number of bytes this server is allowed to use for storage. |
| /raintank/memcache/general/listen_disabled_num | Number of times server has stopped accepting new connections (maxconns). |
| /raintank/memcache/general/time_in_listen_disabled_us | Number of microseconds in maxconns. |
| /raintank/memcache/general/threads | Number of worker threads requested. (see doc/threads.txt) |
| /raintank/memcache/general/conn_yields | Number of times any connection yielded to another due to hitting the -R limit. |
| /raintank/memcache/general/hash_power_level | Current size multiplier for hash table |
| /raintank/memcache/general/hash_bytes | Bytes currently used by hash tables |
| /raintank/memcache/general/expired_unfetched | Items pulled from LRU that were never touched by get/incr/append/etc before expiring |
| /raintank/memcache/general/evicted_unfetched | Items evicted from LRU that were never touched by get/incr/append/etc. |
| /raintank/memcache/general/slabs_moved | Total slab pages moved |
| /raintank/memcache/general/crawler_reclaimed | Total items freed by LRU Crawler |
| /raintank/memcache/general/crawler_items-checked | Total items examined by LRU Crawler |
| /raintank/memcache/general/lrutail_reflocked | Times LRU tail was found with active ref. Items can be evicted to avoid OOM errors. |
| /raintank/memcache/general/moves_to_cold | Items moved from HOT/WARM to COLD LRU's |
| /raintank/memcache/general/moves_to_warm | Items moved from COLD to WARM LRU |
| /raintank/memcache/general/moves_within_lru | Items reshuffled within HOT or WARM LRU's |
| /raintank/memcache/general/direct_reclaims | Times worker threads had to directly reclaim or evict items. |
| /raintank/memcache/general/lru_crawler_starts | Times an LRU crawler was started |
| /raintank/memcache/general/lru_maintainer_juggles | Number of times the LRU bg thread woke up |
| /raintank/memcache/general/slab_global_page_pool | Slab pages returned to global pool for reassignment to other slab classes. |
| /raintank/memcache/general/slab_reassign_rescues | Items rescued from eviction in page move |
| /raintank/memcache/general/slab_reassign_evictions_nomem | Valid items evicted during a page move (due to no free memory in slab) |
| /raintank/memcache/general/slab_reassign_inline_reclaim | Internal stat counter for when the page mover clears memory from the chunk freelist when it wasn't expecting to. |
| /raintank/memcache/general/slab_reassign_busy_items | Items busy during page move, requiring a retry before page can be moved. |
| /raintank/memcache/general/log_worker_dropped | Logs a worker never wrote due to full buf |
| /raintank/memcache/general/log_worker_written | Logs written by a worker, to be picked up |
| /raintank/memcache/general/log_watcher_skipped | Logs not sent to slow watchers. |
| /raintank/memcache/general/log_watcher_sent | Logs written to watchers. |
| /raintank/memcache/settings/maxbytes | Maximum number of bytes allows in this cache |
| /raintank/memcache/settings/maxconns | Maximum number of clients allowed. |
| /raintank/memcache/settings/tcpport | TCP listen port. |
| /raintank/memcache/settings/udpport | UDP listen port. |
| /raintank/memcache/settings/verbosity | 0 = none, 1 = some, 2 = lots |
| /raintank/memcache/settings/oldest | Age of the oldest honored object. |
| /raintank/memcache/settings/umask | umask for the creation of the domain socket. |
| /raintank/memcache/settings/growth_factor | Chunk size growth factor. |
| /raintank/memcache/settings/chunk_size | Minimum space allocated for key+value+flags. |
| /raintank/memcache/settings/num_threads | Number of threads (including dispatch). |
| /raintank/memcache/settings/reqs_per_event | Max num IO ops processed within an event. |
| /raintank/memcache/settings/tcp_backlog | TCP listen backlog. |
| /raintank/memcache/settings/item_size_max | maximum item size |
| /raintank/memcache/settings/hashpower_init | Starting size multiplier for hash table |
| /raintank/memcache/settings/lru_crawler_sleep | Microseconds to sleep between LRU crawls |
| /raintank/memcache/settings/lru_crawler_tocrawl | Max items to crawl per slab per run |
| /raintank/memcache/settings/hot_lru_pct | Pct of slab memory reserved for HOT LRU |
| /raintank/memcache/settings/warm_lru_pct | Pct of slab memory reserved for WARM LRU |
| /raintank/memcache/slabs/*/chunk_size | The amount of space each chunk uses. One item will use one chunk of the appropriate size. |
| /raintank/memcache/slabs/*/chunks_per_page | How many chunks exist within one page. A page by default is less than or equal to one megabyte in size. Slabs are allocated by page, then broken into chunks. |
| /raintank/memcache/slabs/*/total_pages | Total number of pages allocated to the slab class. |
| /raintank/memcache/slabs/*/total_chunks | Total number of chunks allocated to the slab class. |
| /raintank/memcache/slabs/*/get_hits | Total number of get requests serviced by this class. |
| /raintank/memcache/slabs/*/cmd_set | Total number of set requests storing data in this class. |
| /raintank/memcache/slabs/*/delete_hits | Total number of successful deletes from this class. |
| /raintank/memcache/slabs/*/incr_hits | Total number of incrs modifying this class. |
| /raintank/memcache/slabs/*/decr_hits | Total number of decrs modifying this class. |
| /raintank/memcache/slabs/*/cas_hits | Total number of CAS commands modifying this class. |
| /raintank/memcache/slabs/*/cas_badval | Total number of CAS commands that failed to modify a value due to a bad CAS id. |
| /raintank/memcache/slabs/*/touch_hits | Total number of touches serviced by this class. |
| /raintank/memcache/slabs/*/used_chunks | How many chunks have been allocated to items. |
| /raintank/memcache/slabs/*/free_chunks | Chunks not yet allocated to items, or freed via delete. |
| /raintank/memcache/slabs/*/free_chunks_end | Number of free chunks at the end of the last allocated page. |
| /raintank/memcache/slabs/*/mem_requested | Number of bytes requested to be stored in this slab[*]. |
| /raintank/memcache/slabs/total/active_slabs | Total number of slab classes allocated. |
| /raintank/memcache/slabs/total/total_malloced | Total amount of memory allocated to slab pages. |
| /raintank/memcache/items/*/number | Number of items presently stored in this class. Expired items are not automatically excluded. |
| /raintank/memcache/items/*/number_hot | Number of items presently stored in the HOT LRU. |
| /raintank/memcache/items/*/number_warm | Number of items presently stored in the WARM LRU. |
| /raintank/memcache/items/*/number_cold | Number of items presently stored in the COLD LRU. |
| /raintank/memcache/items/*/number_noexp | Number of items presently stored in the NOEXP class. |
| /raintank/memcache/items/*/age | Age of the oldest item in the LRU. |
| /raintank/memcache/items/*/evicted | Number of times an item had to be evicted from the LRU before it expired. |
| /raintank/memcache/items/*/evicted_nonzero | Number of times an item which had an explicit expire time set had to be evicted from the LRU before it expired. |
| /raintank/memcache/items/*/evicted_time | Seconds since the last access for the most recent item evicted from this class. Use this to judge how recently active your evicted data is. |
| /raintank/memcache/items/*/outofmemory | Number of times the underlying slab class was unable to store a new item. This means you are running with -M or an eviction failed. |
| /raintank/memcache/items/*/tailrepairs | Number of times we self-healed a slab with a refcount leak. If this counter is increasing a lot, please report your situation to the developers. |
| /raintank/memcache/items/*/reclaimed | Number of times an entry was stored using memory from an expired entry. |
| /raintank/memcache/items/*/expired_unfetched | Number of expired items reclaimed from the LRU which were never touched after being set. |
| /raintank/memcache/items/*/evicted_unfetched | Number of valid items evicted from the LRU which were never touched after being set. |
| /raintank/memcache/items/*/crawler_reclaimed | Number of items freed by the LRU Crawler. |
| /raintank/memcache/items/*/lrutail_reflocked | Number of items found to be refcount locked in the LRU tail. |
| /raintank/memcache/items/*/moves_to_cold | Number of items moved from HOT or WARM into COLD. |
| /raintank/memcache/items/*/moves_to_warm | Number of items moved from COLD to WARM. |
| /raintank/memcache/items/*/moves_within_lru | Number of times active items were bumped within HOT or WARM. |
| /raintank/memcache/items/*/direct_reclaims | Number of times worker threads had to directly pull LRU tails to find memory for a new item. |
The list of available metrics might vary depending on the Memcache version or the system configuration.