Memcached Exporter for Prometheus

A memcached exporter for prometheus.

Building

The memcached exporter exports metrics from a memcached server for consumption by prometheus. The server is specified as --memcached.address flag to the program (default is localhost:11211).

By default the memcache_exporter serves on port 0.0.0.0:9150 at /metrics

Add monitor multiple instances per exporter

--memcached.address="127.0.0.1:11211,127.0.0.1:11212"

# HELP memcached_uptime_seconds Number of seconds since the server started.
# TYPE memcached_uptime_seconds counter
memcached_uptime_seconds{server="127.0.0.1:11211"} 1355
memcached_uptime_seconds{server="127.0.0.1:11212"} 1352
# HELP memcached_version The version of this memcached server.
# TYPE memcached_version gauge
memcached_version{server="127.0.0.1:11211",version="1.5.12"} 1
memcached_version{server="127.0.0.1:11212",version="1.5.12"} 1
# HELP memcached_written_bytes_total Total number of bytes sent by this server to network.
# TYPE memcached_written_bytes_total counter
memcached_written_bytes_total{server="127.0.0.1:11211"} 139454
memcached_written_bytes_total{server="127.0.0.1:11212"} 141395

make
./memcached_exporter

Alternatively a Dockerfile is supplied

docker run -p 9150:9150 quay.io/prometheus/memcached-exporter:v0.5.0

Collectors

The exporter collects a number of statistics from the server:

# HELP memcached_commands_total Total number of all requests broken down by command (get, set, etc.) and status.
# TYPE memcached_commands_total counter
# HELP memcached_connections_total Total number of connections opened since the server started running.
# TYPE memcached_connections_total counter
# HELP memcached_connections_yielded_total Total number of connections yielded running due to hitting the memcached's -R limit.
# TYPE memcached_connections_yielded_total counter
# HELP memcached_connections_listener_disabled_total Number of times that memcached has hit its connections limit and disabled its listener.
# TYPE memcached_connections_listener_disabled_total counter
# HELP memcached_current_bytes Current number of bytes used to store items.
# TYPE memcached_current_bytes gauge
# HELP memcached_current_connections Current number of open connections.
# TYPE memcached_current_connections gauge
# HELP memcached_current_items Current number of items stored by this instance.
# TYPE memcached_current_items gauge
# HELP memcached_items_evicted_total Total number of valid items removed from cache to free memory for new items.
# TYPE memcached_items_evicted_total counter
# HELP memcached_items_reclaimed_total Total number of times an entry was stored using memory from an expired entry.
# TYPE memcached_items_reclaimed_total counter
# HELP memcached_items_total Total number of items stored during the life of this instance.
# TYPE memcached_items_total counter
# HELP memcached_limit_bytes Number of bytes this server is allowed to use for storage.
# TYPE memcached_limit_bytes gauge
# HELP memcached_malloced_bytes Number of bytes of memory allocated to slab pages.
# TYPE memcached_malloced_bytes gauge
# HELP memcached_max_connections Maximum number of clients allowed.
# TYPE memcached_max_connections gauge
# HELP memcached_read_bytes_total Total number of bytes read by this server from network.
# TYPE memcached_read_bytes_total counter
# HELP memcached_slab_chunk_size_bytes Number of bytes allocated to each chunk within this slab class.
# TYPE memcached_slab_chunk_size_bytes gauge
# HELP memcached_slab_chunks_free Number of chunks not yet allocated items.
# TYPE memcached_slab_chunks_free gauge
# HELP memcached_slab_chunks_free_end Number of free chunks at the end of the last allocated page.
# TYPE memcached_slab_chunks_free_end gauge
# HELP memcached_slab_chunks_per_page Number of chunks within a single page for this slab class.
# TYPE memcached_slab_chunks_per_page gauge
# HELP memcached_slab_chunks_used Number of chunks allocated to an item.
# TYPE memcached_slab_chunks_used gauge
# HELP memcached_slab_commands_total Total number of all requests broken down by command (get, set, etc.) and status per slab.
# TYPE memcached_slab_commands_total counter
# HELP memcached_slab_current_chunks Number of chunks allocated to this slab class.
# TYPE memcached_slab_current_chunks gauge
# HELP memcached_slab_current_items Number of items currently stored in this slab class.
# TYPE memcached_slab_current_items gauge
# HELP memcached_slab_current_pages Number of pages allocated to this slab class.
# TYPE memcached_slab_current_pages gauge
# HELP memcached_slab_items_age_seconds Number of seconds the oldest item has been in the slab class.
# TYPE memcached_slab_items_age_seconds gauge
# HELP memcached_slab_items_crawler_reclaimed_total Total number of items freed by the LRU Crawler.
# TYPE memcached_slab_items_crawler_reclaimed_total counter
# HELP memcached_slab_items_evicted_nonzero_total Total number of times an item which had an explicit expire time set had to be evicted from the LRU before it expired.
# TYPE memcached_slab_items_evicted_nonzero_total counter
# HELP memcached_slab_items_evicted_time_seconds Seconds since the last access for the most recent item evicted from this class.
# TYPE memcached_slab_items_evicted_time_seconds counter
# HELP memcached_slab_items_evicted_total Total number of times an item had to be evicted from the LRU before it expired.
# TYPE memcached_slab_items_evicted_total counter
# HELP memcached_slab_items_evicted_unfetched_total Total nmber of items evicted and never fetched.
# TYPE memcached_slab_items_evicted_unfetched_total counter
# HELP memcached_slab_items_expired_unfetched_total Total number of valid items evicted from the LRU which were never touched after being set.
# TYPE memcached_slab_items_expired_unfetched_total counter
# HELP memcached_slab_items_outofmemory_total Total number of items for this slab class that have triggered an out of memory error.
# TYPE memcached_slab_items_outofmemory_total counter
# HELP memcached_slab_items_reclaimed_total Total number of items reclaimed.
# TYPE memcached_slab_items_reclaimed_total counter
# HELP memcached_slab_items_tailrepairs_total Total number of times the entries for a particular ID need repairing.
# TYPE memcached_slab_items_tailrepairs_total counter
# HELP memcached_slab_mem_requested_bytes Number of bytes of memory actual items take up within a slab.
# TYPE memcached_slab_mem_requested_bytes gauge
# HELP memcached_up Could the memcached server be reached.
# TYPE memcached_up gauge
# HELP memcached_uptime_seconds Number of seconds since the server started.
# TYPE memcached_uptime_seconds counter
# HELP memcached_version The version of this memcached server.
# TYPE memcached_version gauge
# HELP memcached_written_bytes_total Total number of bytes sent by this server to network.
# TYPE memcached_written_bytes_total counter

There is also optional support to export metrics about the memcached process itself by setting the --memcached.pid-file <path> flag. If the memcached_exporter process has the rights to read /proc information of the memcached process, then the following metrics will be exported additionally.

# HELP memcached_process_cpu_seconds_total Total user and system CPU time spent in seconds.
# TYPE memcached_process_cpu_seconds_total counter
# HELP memcached_process_max_fds Maximum number of open file descriptors.
# TYPE memcached_process_max_fds gauge
# HELP memcached_process_open_fds Number of open file descriptors.
# TYPE memcached_process_open_fds gauge
# HELP memcached_process_resident_memory_bytes Resident memory size in bytes.
# TYPE memcached_process_resident_memory_bytes gauge
# HELP memcached_process_start_time_seconds Start time of the process since unix epoch in seconds.
# TYPE memcached_process_start_time_seconds gauge
# HELP memcached_process_virtual_memory_bytes Virtual memory size in bytes.
# TYPE memcached_process_virtual_memory_bytes gauge