Difference between revisions of "Memcached List all Keys"

Latest revision as of 14:43, 22 August 2015

Memcached List all Keys

In the general case, there is no way to list all the keys that a memcached instance is storing. You can, however, list something like the first 1Meg of keys, which is usually enough during development.

Connect to your Memcached Instance

We have multiple ways to set up memcache instances (tcp or socket)

Connect to Memcached TCP Instance

telnet 127.0.0.1 11211

Connect to Memcached Socket Instance

nc -U /path/to/socket

Now we need to get the slab ids

List the items to get the slab id:

stats items

STAT items:5:number 2
STAT items:5:age 1390736
STAT items:5:evicted 0
STAT items:5:evicted_nonzero 0
STAT items:5:evicted_time 0
STAT items:5:outofmemory 0
STAT items:5:tailrepairs 0
STAT items:6:number 260
STAT items:6:age 1385409
STAT items:6:evicted 0
STAT items:6:evicted_nonzero 0
STAT items:6:evicted_time 0
STAT items:6:outofmemory 0
STAT items:6:tailrepairs 0

The first number after ‘items’ is the slab id. Request a cache dump for each slab id, with a limit for the max number of keys to dump:

stats cachedump 3 100
ITEM views.briansnelson.cache.cache_header..cc7d9 [6 b; 1256056128 s]
END

stats cachedump 22 100
ITEM views.briansnelson.cache.cache_page..8427e [7736 b; 1256056128 s]
END

Now you should be able to list and view the keys