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Memcached Integration

Memcached protocol datasources related to request/response are available out-of-the-box within the AOC. Please look at pre-canned dashboards for Memcached or use the Analytics Sandbox to plot charts without any additional configuration.

Note: Protocol metrics are captured by collectors running with EPOCH_ANALYSIS_DEPTH=layer7 set in their configuration.

In order to access infrastructure datasources, follow the steps listed in the infrastructure integration section below.

Protocol Integration

Attributes

Below attributes can be used in filters and group by operations in analytics within alerts, dashboards, etc.

Metric Description Value / Example
memcached.command.name Client command name GET, SET, FLUSH, QUIT. See full list
memcached.response Server response DELETED, NOT FOUND. See full details
memcached.command.type There are 3 command types
  • Storage : ask server to store data identified by a key
  • Retrieval : get data identified by a key
  • Others : operations on the data such as touch, delete, etc.
See full details on command types
STORAGE, RETRIEVAL, OTHERS

In addition, there are some shared attributes that are common across all integrations.

Protocol Datasources

Datasource Available Aggregations Unit Description
memcached.request_response.latency sum avg min max std_dev millisecond The aggregated latency across all Memcached request/response.
memcached.request_response.throughput throughput /s The total number of Memcached request/response per second.
memcached.request_response.count count The total number of Memcached request/response.
memcached.request.bytes sum avg min max byte The aggregated number of bytes across all Memcached requests.
memcached.request.bytes.rate rate byte/s The rate of bytes transferred across all Memcached requests.
memcached.request.count count The total number of Memcached requests.
memcached.request.packets sum avg min max packet The aggregated number of packets across all Memcached requests.
memcached.request.packets.rate rate packet/s The rate of packets transferred across all Memcached requests.
memcached.request.throughput throughput /s The rate of total number of Memcached requests.
memcached.response.bytes sum avg min max byte The aggregated number of bytes across all Memcached responses.
memcached.response.bytes.rate rate byte/s The rate of bytes transferred across all Memcached responses.
memcached.response.count count The total number of Memcached responses.
memcached.response.packets sum avg min max packet The aggregated number of packets across all Memcached responses.
memcached.response.packets.rate rate packet/s The rate of packets transferred across all Memcached responses.
memcached.response.throughput throughput /s The rate of total number of Memcached responses.

Infrastructure Integration

Instructions

Follow the installation guide below for your given collector environment.

During installation, use the configuration section below as reference.

After installation, the infrastructure datasources in the table below will be available in the AOC.

Installation Guide

Installing this integration consists of creating a yaml file in the filesystem of your collectors. Click below for instructions on how to do so for your given collectors environment.

Docker

Kubernetes

Mesos-Marathon

Debian

Ubuntu

RHEL/CentOS

Configuration

Edit mcache.yaml to configure the agent. Please refer mcache.yaml for all available configuration options.

    init_config:
    instances:
      - url: localhost  # url used to connect to the memcached instance
        port: 11211 # If this line is not present, the port will default to 11211
        tags:
          - 'instance:instance_tag'
          - optional_regular_tag

Infrastructure Datasources

Datasource Available Aggregations Unit Description
memcache.avg_item_size avg max min sum byte The average size of an item.
memcache.bytes avg max min sum byte Current number of bytes used by this server to store items.
memcache.bytes_read_rate avg max min sum byte/second Rate of bytes read from the network by this server.
memcache.bytes_written_rate avg max min sum byte/second Rate of bytes written to the network by this server.
memcache.cas_badval_rate avg max min sum key/second Rate at which keys are compared and swapped where the comparison (original) value did not match the supplied value.
memcache.cas_hits_rate avg max min sum hit/second Rate at which keys are compared and swapped and found present.
memcache.cas_misses_rate avg max min sum miss/second Rate at which keys are compared and swapped and not found present.
memcache.cmd_flush_rate avg max min sum command/second Rate of "flush_all" commands.
memcache.cmd_get_rate avg max min sum command/second Rate of "get" commands.
memcache.cmd_set_rate avg max min sum command/second Rate of "set" commands.
memcache.connection_structures avg max min sum Number of connection structures allocated by the server.
memcache.curr_connections avg max min sum connection Number of open connections to this server.
memcache.curr_items avg max min sum item Current number of items stored by the server.
memcache.delete_hits_rate avg max min sum hit/second Rate at which delete commands result in items being removed.
memcache.delete_misses_rate avg max min sum miss/second Rate at which delete commands result in no items being removed.
memcache.evictions_rate avg max min sum eviction/second Rate at which valid items are removed from cache to free memory for new items.
memcache.fill_percent avg max min sum percent Amount of memory being used by the server for storing items as a percentage of the max allowed.
memcache.get_hit_percent avg max min sum percent Percentage of requested keys that are found present.
memcache.get_hits_rate avg max min sum hit/second Rate at which keys are requested and found present.
memcache.get_misses_rate avg max min sum miss/second Rate at which keys are requested and not found.
memcache.limit_maxbytes avg max min sum byte Number of bytes this server is allowed to use for storage.
memcache.listen_disabled_num_rate avg max min sum event/second Rate at which the server has reached the max connection limit.
memcache.pointer_size avg max min sum bit Default size of pointers on the host OS (generally 32 or 64)
memcache.rusage_system_rate avg max min sum fraction Fraction of user time the CPU spent executing this server process.
memcache.rusage_user_rate avg max min sum fraction Fraction of time the CPU spent executing kernel code on behalf of this server process.
memcache.threads avg max min sum thread Number of threads used by the current Memcached server process.
memcache.total_connections_rate avg max min sum connection/second Rate at which connections to this server are opened.
memcache.total_items avg max min sum item Total number of items stored by this server since it started.
memcache.uptime avg max min sum second Number of seconds this server has been running.
memcache.items.evicted_rate avg max min sum eviction/second Rate st which items had to be evicted from the LRU before expiring
memcache.items.evicted_nonzero_rate avg max min sum eviction/second Rate at which nonzero items which had an explicit expire time set had to be evicted from the LRU before expiring
memcache.items.expired_unfetched_rate avg max min sum eviction/second Rate at which expired items reclaimed from the LRU which were never touched after being set
memcache.items.evicted_unfetched_rate avg max min sum eviction/second Rate at which valid items evicted from the LRU which were never touched after being set
memcache.items.outofmemory_rate avg max min sum error/second Rate at which the underlying slab class was unable to store a new item
memcache.items.tailrepairs_rate avg max min sum operation/second Rate at which memcache self-healed a slab with a refcount leak
memcache.items.moves_to_cold_rate avg max min sum item/second Rate at which items were moved from HOT or WARM into COLD
memcache.items.moves_to_warm_rate avg max min sum item/second Rate at which items were moved from COLD to WARM
memcache.items.moves_within_lru_rate avg max min sum item/second Rate at which active items were bumped within HOT or WARM
memcache.items.reclaimed_rate avg max min sum operation/second Rate at which entries were stored using memory from an expired entry
memcache.items.crawler_reclaimed_rate avg max min sum operation/second Rate at which items freed by the LRU Crawler
memcache.items.lrutail_reflocked_rate avg max min sum item/second Rate at which items found to be refcount locked in the LRU tail
memcache.items.direct_reclaims_rate avg max min sum operation/second Rate at which worker threads had to directly pull LRU tails to find memory for a new item
memcache.items.number avg max min sum item Number of items presently stored in this slab class
memcache.items.number_hot avg max min sum item Number of items presently stored in the HOT LRU
memcache.items.number_warm avg max min sum item Number of items presently stored in the WARM LRU
memcache.items.number_cold avg max min sum item Number of items presently stored in the COLD LRU
memcache.items.number_noexp avg max min sum item Number of items presently stored in the NOEXP class
memcache.items.age avg max min sum second Age of the oldest item in the LRU
memcache.items.evicted_time avg max min sum second Seconds since the last access for the most recent item evicted from this class
memcache.slabs.get_hits_rate avg max min sum hit/second Rate at which get requests were serviced by this slab class
memcache.slabs.cmd_set_rate avg max min sum command/second Rate at which set requests stored data in this slab class
memcache.slabs.delete_hits_rate avg max min sum operation/second Rate at which delete commands succeeded in this slab class
memcache.slabs.incr_hits_rate avg max min sum operation/second Rate at which incrs commands modified this slab class
memcache.slabs.decr_hits_rate avg max min sum operation/second Rate at which decrs commands modified this slab class
memcache.slabs.cas_hits_rate avg max min sum operation/second Rate at which CAS commands modified this slab class
memcache.slabs.cas_badval_rate avg max min sum key/second Rate at which CAS commands failed to modify a value due to a bad CAS id
memcache.slabs.touch_hits_rate avg max min sum operation/second Rate of touches serviced by this slab class
memcache.slabs.used_chunks_rate avg max min sum buffer/second Rate at which chunks have been allocated to items
memcache.slabs.chunk_size avg max min sum byte The amount of space each chunk uses
memcache.slabs.chunks_per_page avg max min sum buffer How many chunks exist within one page
memcache.slabs.total_pages avg max min sum page Total number of pages allocated to the slab class
memcache.slabs.total_chunks avg max min sum buffer Total number of chunks allocated to the slab class
memcache.slabs.used_chunks avg max min sum buffer How many chunks have been allocated to items
memcache.slabs.free_chunks avg max min sum buffer Chunks not yet allocated to items or freed via delete
memcache.slabs.free_chunks_end avg max min sum buffer Number of free chunks at the end of the last allocated page
memcache.slabs.mem_requested avg max min sum byte Number of bytes requested to be stored in this slab
memcache.slabs.active_slabs avg max min sum occurrence Total number of slab classes allocated
memcache.slabs.total_malloced avg max min sum byte Total amount of memory allocated to slab pages