Memcached
Memcached 采集器可以从 Memcached 实例中采集实例运行状态指标，并将指标采集到观测云，帮助监控分析 Memcached 各种异常情况。
配置¶
前置条件¶
- Memcached 版本 >=
1.5.0。已测试的版本：- 1.5.x
- 1.6.x
进入 DataKit 安装目录下的 conf.d/samples 目录，复制 memcached.conf.sample 并命名为 memcached.conf。示例如下：
[[inputs.memcached]]
## Servers' addresses.
servers = ["localhost:11211"]
# unix_sockets = ["/var/run/memcached.sock"]
## Set true to enable election
election = true
## Collect extra stats
# extra_stats = ["slabs", "items"]
## Collect interval.
# units: "ns", "us", "ms", "s", "m", "h"
interval = "10s"
[inputs.memcached.tags]
# some_tag = "some_value"
# more_tag = "some_other_value"
# ...
配置好后，重启 DataKit 即可。
目前可以通过 ConfigMap 方式注入采集器配置来开启采集器。
指标¶
以下所有数据采集，默认会追加全局选举 tag，也可以在配置中通过 [inputs.memcached.tags] 指定其它标签：
memcached¶
| Tags & Fields | Description |
|---|---|
| server ( tag) |
The memcached server address from which metrics are gathered. |
| accepting_conns | Whether the server is currently accepting new connections. 1 means accepting, 0 means not accepting.Type: int | (gauge) Unit: N/A |
| auth_cmds | Cumulative number of authentication commands handled, successful or failed. Type: int | (count) Unit: count |
| auth_errors | Cumulative number of failed authentications. Type: int | (count) Unit: count |
| bytes | Current number of bytes used to store items Type: int | (gauge) Unit: digital,B |
| bytes_read | Cumulative bytes read by this server from the network. Type: int | (count) Unit: digital,B |
| bytes_written | Cumulative bytes written by this server to the network. Type: int | (count) Unit: digital,B |
| cas_badval | Cumulative CAS requests for which a key was found but the CAS value did not match. Type: int | (count) Unit: count |
| cas_hits | Cumulative successful CAS requests. Type: int | (count) Unit: count |
| cas_misses | Cumulative CAS requests against missing keys. Type: int | (count) Unit: count |
| cmd_flush | Cumulative number of flush requests. Type: int | (count) Unit: count |
| cmd_get | Cumulative number of retrieval requests. Type: int | (count) Unit: count |
| cmd_set | Cumulative number of storage requests. Type: int | (count) Unit: count |
| cmd_touch | Cumulative number of touch requests. Type: int | (count) Unit: count |
| conn_yields | Cumulative number of times a connection yielded to another connection after hitting the -R limit.Type: int | (count) Unit: count |
| connection_structures | Number of connection structures allocated by the server Type: int | (gauge) Unit: count |
| curr_connections | Number of open connections Type: int | (gauge) Unit: count |
| curr_items | Current number of items stored Type: int | (gauge) Unit: count |
| decr_hits | Cumulative successful decr requests.Type: int | (count) Unit: count |
| decr_misses | Cumulative decr requests against missing keys.Type: int | (count) Unit: count |
| delete_hits | Cumulative delete requests that removed an item. Type: int | (count) Unit: count |
| delete_misses | Cumulative delete requests for missing keys. Type: int | (count) Unit: count |
| evicted_unfetched | Cumulative items evicted from the LRU that were never fetched after being set. Type: int | (count) Unit: count |
| evictions | Cumulative valid items removed from cache to free memory for new items. Type: int | (count) Unit: count |
| expired_unfetched | Cumulative expired items reclaimed from the LRU that were never fetched after being set. Type: int | (count) Unit: count |
| get_hits | Cumulative keys requested and found present. Type: int | (count) Unit: count |
| get_misses | Cumulative requested items that were not found. Type: int | (count) Unit: count |
| hash_bytes | Bytes currently used by hash tables Type: int | (gauge) Unit: digital,B |
| hash_is_expanding | Whether the hash table is currently being grown to a new size. 1 means expanding, 0 means not expanding.Type: int | (gauge) Unit: N/A |
| hash_power_level | Current size multiplier for hash table Type: int | (gauge) Unit: count |
| incr_hits | Cumulative successful incr requests.Type: int | (count) Unit: count |
| incr_misses | Cumulative incr requests against missing keys.Type: int | (count) Unit: count |
| limit_maxbytes | Number of bytes this server is allowed to use for storage Type: int | (gauge) Unit: digital,B |
| listen_disabled_num | Cumulative number of times the server stopped accepting new connections after reaching maxconns.Type: int | (count) Unit: count |
| reclaimed | Cumulative entries stored using memory reclaimed from an expired entry. Type: int | (count) Unit: count |
| threads | Number of worker threads requested Type: int | (gauge) Unit: count |
| total_connections | Cumulative connections opened since the server started. Type: int | (count) Unit: count |
| total_items | Cumulative items stored since the server started. Type: int | (count) Unit: count |
| touch_hits | Cumulative keys touched with a new expiration time. Type: int | (count) Unit: count |
| touch_misses | Cumulative touch requests for items that were not found. Type: int | (count) Unit: count |
| uptime | Seconds since the server started. Type: int | (gauge) Unit: time,s |
memcached_items¶
| Tags & Fields | Description |
|---|---|
| server ( tag) |
The memcached server address from which metrics are gathered. |
| slab_id ( tag) |
Slab class ID from the stats items key. |
| age | Age in seconds of the oldest item in the LRU for this slab class. Type: int | (gauge) Unit: time,s |
| crawler_reclaimed | Cumulative items freed by the LRU crawler. Type: int | (count) Unit: count |
| direct_reclaims | Cumulative worker threads that directly pulled LRU tails to find memory for a new item. Type: int | (count) Unit: count |
| evicted | Cumulative items evicted from this slab class before expiring. Type: int | (count) Unit: count |
| evicted_nonzero | Cumulative evicted items from this slab class that had an explicit non-zero expiration time. Type: int | (count) Unit: count |
| evicted_time | Seconds since the last access for the most recent item evicted from this class Type: int | (gauge) Unit: time,s |
| evicted_unfetched | Cumulative valid items evicted from this slab class that were never fetched after being set. Type: int | (count) Unit: count |
| expired_unfetched | Cumulative expired items reclaimed from this slab class that were never fetched after being set. Type: int | (count) Unit: count |
| lrutail_reflocked | Cumulative items found to be refcount locked in the LRU tail.Type: int | (count) Unit: count |
| moves_to_cold | Cumulative items moved from HOT or WARM into COLD. Type: int | (count) Unit: count |
| moves_to_warm | Cumulative items moved from COLD to WARM. Type: int | (count) Unit: count |
| moves_within_lru | Cumulative active items bumped within HOT or WARM. Type: int | (count) Unit: count |
| number | Number of items presently stored in this slab class Type: int | (gauge) Unit: count |
| number_cold | Number of items presently stored in the COLD LRU Type: int | (gauge) Unit: count |
| number_hot | Number of items presently stored in the HOT LRU Type: int | (gauge) Unit: count |
| number_noexp | Number of items presently stored in the NOEXP classType: int | (gauge) Unit: count |
| number_warm | Number of items presently stored in the WARM LRU Type: int | (gauge) Unit: count |
| outofmemory | Cumulative times this slab class could not store a new item due to memory pressure. Type: int | (count) Unit: count |
| reclaimed | Cumulative entries stored using memory reclaimed from an expired entry. Type: int | (count) Unit: count |
| tailrepairs | Cumulative self-healing repairs for slab items with leaked refcount references.Type: int | (count) Unit: count |
memcached_slabs¶
| Tags & Fields | Description |
|---|---|
| server ( tag) |
The memcached server address from which metrics are gathered. |
| slab_id ( tag) |
Slab class ID from the stats slabs key. |
| active_slabs | Total number of slab classes allocated Type: int | (gauge) Unit: count |
| cas_badval | Cumulative CAS commands that failed to modify a value due to a bad CAS ID. Type: int | (count) Unit: count |
| cas_hits | Cumulative CAS commands that modified this slab class. Type: int | (count) Unit: count |
| chunk_size | The amount of space each chunk uses Type: int | (gauge) Unit: digital,B |
| chunks_per_page | How many chunks exist within one page Type: int | (gauge) Unit: count |
| cmd_set | Cumulative set requests that stored data in this slab class. Type: int | (count) Unit: count |
| decr_hits | Cumulative decr commands that modified this slab class.Type: int | (count) Unit: count |
| delete_hits | Cumulative successful delete commands in this slab class. Type: int | (count) Unit: count |
| free_chunks | Chunks not yet allocated to items or freed via delete Type: int | (gauge) Unit: count |
| free_chunks_end | Number of free chunks at the end of the last allocated page Type: int | (gauge) Unit: count |
| get_hits | Cumulative get requests serviced by this slab class. Type: int | (count) Unit: count |
| incr_hits | Cumulative incr commands that modified this slab class.Type: int | (count) Unit: count |
| total_chunks | Total number of chunks allocated to the slab class Type: int | (gauge) Unit: count |
| total_malloced | Total amount of memory allocated to slab pages Type: int | (gauge) Unit: digital,B |
| total_pages | Total number of pages allocated to the slab class Type: int | (gauge) Unit: count |
| touch_hits | Cumulative touch commands serviced by this slab class. Type: int | (count) Unit: count |
| used_chunks | How many chunks have been allocated to items Type: int | (gauge) Unit: count |