Memcached Metrics with InstrumentalD
The best way to get Memcached metrics into Instrumental is with InstrumentalD, the fast and reliable server agent created by the Instrumental team. By using InstrumentalD to collect Memcached metrics, you'll get premade Memcached graphs and unlock the full power of our Query Language.
- Quick Start
- Configuring InstrumentalD
- Memcached Metrics Collected
- How many metrics can I expect from InstrumentalD?
- Dashboard
Quick Start
Check out our Installation Instructions for more details. Otherwise, here's the bare minimum to get up and running.
brew install instrumental/instrumentald/instrumentald echo 'memcached = ["localhost:11211"]' >> instrumentald.toml instrumentald -c instrumentald.toml -k PROJECT_TOKEN
curl https://packagecloud.io/install/repositories/expectedbehavior/instrumental/script.deb.sh | sudo bash sudo apt-get install instrumentald echo 'project_token = "PROJECT_TOKEN"' | sudo tee /etc/instrumentald.toml echo 'memcached = ["localhost:11211"]' | sudo tee -a /etc/instrumentald.toml sudo systemctl restart instrumentald
curl https://packagecloud.io/install/repositories/expectedbehavior/instrumental/script.rpm.sh | sudo bash sudo yum install instrumentald echo 'project_token = "PROJECT_TOKEN"' | sudo tee /etc/instrumentald.toml echo 'memcached = ["localhost:11211"]' | sudo tee -a /etc/instrumentald.toml sudo service instrumentald restart
Configuring InstrumentalD
InstrumentalD collects the metrics below from as many Memcached servers as configured. Here's a basic example of the Memcached config:
memcached = ["localhost:11211"]
Everything you need to know about configuring InstrumentalD, including more information about Memcached config, can be found in the InstrumentalD Configuration docs.
Metrics Collected
Memcached metrics collected by InstrumentalD follow this pattern:
memcached.<host from connection string>.<metric>
bytes |
Bytes currently used for caching items |
---|---|
bytes_read |
Number of inbound bytes received by this server since startup |
bytes_written |
Number of outbound bytes sent by this server since startup |
cas_hits |
Number of successful "cas" commands since startup |
cas_misses |
Number of failed "cas" commands since startup |
cmd_get |
Number of "get" commands received since server startup not counting if they were successful or not |
cmd_set |
Number of "set" commands serviced since startup |
conn_yields |
The number of times any client has hit the maximum number of requests per event limit (-R on command line) |
curr_connections |
Number of open connections to this memcached server |
curr_items |
Number of items currently in this server's cache |
decr_hits |
Number of "decr" calls to existing keys |
decr_misses |
Number of "decr" command calls to undefined keys |
delete_hits |
Number of "delete" calls to existing keys |
delete_misses |
Number of "delete" commands for keys not existing within the cache |
evictions |
Number of objects removed from the cache to free up memory for new items because memcached reached it's maximum memory setting (limit_maxbytes) |
get_hits |
Number of successful "get" commands (cache hits) since startup |
get_misses |
Number of failed "get" commands (cache misses) since startup |
incr_hits |
Number of successful "incr" commands since startup |
incr_misses |
Number of failed "incr" commands since startup |
limit_maxbytes |
Maximum configured cache size in bytes |
How many metrics can I expect from InstrumentalD?
InstrumentalD will collect 20 metrics for each server configured.
Dashboard
Here are the graphs included in our Memcached Dashboard. It's a great way to get started visualizing these metrics.