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Message-ID: <4C804E8E.1020105@softwareprojects.com>
Date: Thu, 02 Sep 2010 21:25:34 -0400
From: Mike Peters <cassandra@softwareprojects.com>
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To: user@cassandra.apache.org
Subject: 4k keyspaces...  Maybe we're doing it wrong?
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  Hi,

We're in the process of migrating 4,000 MySQL client databases to 
Cassandra.  All database schemas are identical.

With MySQL, we used to provision a separate 'database' per each client, 
to make it easier to shard and move things around.

Does it make sense to migrate the 4,000 MySQL databases to 4,000 
keyspaces in Cassandra?  Or should we stick with a single keyspace?

My concerns are -
#1. Will every single node end up with 4k folders under /cassandra/data/?

#2. Performance: Will Cassandra work better with a single keyspace + 
lots of keys, or thousands of keyspaces?

-

Granted it's 'cleaner' to have a separate keyspace per each client, but 
maybe that's not the best approach with Cassandra.

Thoughts?