Memcached is a high-performance, distributed memory object caching system used to speed up dynamic web applications by reducing database load. This cheatsheet serves as a quick reference for common Memcached commands and configurations.
| Command | Description |
|---|---|
memcached |
Start Memcached server |
memcached -d -p 11211 |
Start Memcached daemon on port 11211 |
telnet localhost 11211 |
Connect to Memcached server |
set key 0 60 5 |
Store a value with key, flags, expiration, and size |
add key 0 60 5 |
Add a value only if the key does not exist |
replace key 0 60 8 |
Replace a value only if the key exists |
append key 0 60 3 |
Append data to an existing value |
prepend key 0 60 4 |
Prepend data to an existing value |
cas key 0 60 9 |
Compare and swap - update if the value hasn’t changed |
get key |
Retrieve the value associated with the key |
gets key |
Retrieve the value and its unique CAS identifier |
delete key |
Remove the key and its value |
incr key 2 |
Increment the value of the key by 2 |
decr key 1 |
Decrement the value of the key by 1 |
flush_all |
Flush all items from the cache |
stats |
Display server statistics |
version |
Display Memcached version |
quit |
Close the connection to the Memcached server |
stats reset |
Reset server statistics |
stats items |
Display item-related statistics |
stats slabs |
Display slab-related statistics |
stats sizes |
Display sizes-related statistics |
stats detail on |
Enable verbose mode for statistics |
stats detail off |
Disable verbose mode for statistics |
touch key 120 |
Update the expiration time for the key |
flush_all 5 |
Flush all items after a delay of 5 seconds |
verbosity 2 |
Set server verbosity level |
lru_crawler metadump 1 |
Request a dump of the metadata |
lru_crawler enable |
Enable the LRU crawler background job |
lru_crawler disable |
Disable the LRU crawler background job |
config get maxbytes |
Retrieve the configured maximum memory size |
config set maxbytes 67108864 |
Set the maximum memory size to 64MB |
slabs reassign 0 1 |
Move items from slab class 0 to slab class 1 |
watch key |
Watch the key for modifications |
stats cachedump 0 0 |
Dump all items from slab class 0 |
stats cachedump 1 0 |
Dump all items from slab class 1 |
stats cachedump 2 100 |
Dump up to 100 items from slab class 2 |
config get slab_automove |
Retrieve slab automove settings |
config set slab_automove 1 |
Enable slab automove |
config set slab_automove 0 |
Disable slab automove |
config get tail_repair_time |
Retrieve tail-fragmentation avoidance settings |
config set tail_repair_time 30 |
Set tail-fragmentation avoidance time to 30 seconds |
version |
Display Memcached version |
Note: Adjust the parameters (e.g., key, flags, expiration) based on your specific use case. Always refer to the official Memcached documentation for detailed information.