Listing all keys on a server: why?

[Jamie McCarthy]

Hi everyone,

Every once in a while I hear people musing that it'd be useful to get a
list of all keys currently available in a memcached server.  If you're
one of those people, please email me off-list, I'd like to kick ideas
around with you.

My current thinking is that, since:

* one or more memcached servers may be down when you get your list
  and come back up immediately afterwards
* whatever you want the list for, it's not atomic with your next
  memcached operation anyway

...the list you would get would be obsolete as soon as you got it.  So
my guess would be that, if you think you need that list, you may be
wanting to do something with memcached that you can't really do.  But my
guesses are frequently wrong and if there's something I'm forgetting
please email me and let me know.  Thanks.