> Third, since all keys are hashed, you'll find that your items will be
evenly distributed so unless your nodes have different amounts of
memory, they will fill up at approximately the same pace.

Can you tell me a little bit more about how this part works?  What does hashing 
the key against the list of servers mean?  How does hashing alllow the servers 
to fill up at approximately the same pace?

Thanks


Date: Sat, 30 May 2009 10:16:46 +0200
Subject: Re: How does memcached load balance or does it?
From: [email protected]
To: [email protected]

Well, first of all, it doesn't ensure that. There's no communication between 
memcached nodes in a cluster, which is what makes it scale linearly.

Second, you shouldn't worry about a node filling up. It's a cache, not a 
data-store, the least recently used items will be evicted when you fill up a 
node.


Third, since all keys are hashed, you'll find that your items will be evenly 
distributed so unless your nodes have different amounts of memory, they will 
fill up at approximately the same pace.


/Henrik


On Sat, May 30, 2009 at 07:05, scranthdaddy <[email protected]> wrote:



The documentation states "When doing a memcached lookup, first the

client hashes the key against the whole list of servers. Once it has

chosen a server, the client then sends its request, and the server

does an internal hash key lookup for the actual item data. "



My question is how then does memcache ensure that a node in the

cluster doesnt fill up?



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