Multiple caches in memcached?
sgrimm at facebook.com
Wed Aug 2 09:25:15 UTC 2006
FYI, there is no command in memcached to list all the keys in the cache,
so whether you use one cache or two you are going to need a different
There is a command intended for debugging that will list keys, but it
has a hard limit on the size of the list and will only list keys up to
that limit, even if there are more in the cache. And you don't want to
use it frequently because it will make your cache unresponsive while it
composes its output. (Like I said, it's intended for debugging of
memcached internals, where that's not an issue.)
This comes up on the mailing list a lot -- read the archive for just
about any month and you will find a discussion of why memcached doesn't
support a "list keys" operation.
Abhishek Pokharna wrote:
> - I do not want to iterate each and every key and there then decide
> whether its a user or a group .I could have so many users or group
> entries.The thing here is that I dont have the keys i need to
> iterate.I would want to iterate on every User entity or group entity
> Suppose I have 1000 users and 2000 groups in one cache,and if i just
> needed all the 1000 users, I would unnessary iterate 3000 keys.
More information about the memcached