incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Mark Reddy <>
Subject Re: Reasonable range for the max number of tables?
Date Tue, 05 Aug 2014 09:24:04 GMT
Hi Phil,

In theory, the max number of column families would be in the low number of
hundreds. In practice the limit is related the amount of heap you have, as
each column family will consume 1 MB of heap due to arena allocation.

To segregate customer data, you could:
- Use customer specific column families under a single keyspace
- Use a keyspace per customer
- Use the same column families and have a column that identifies the
customer. On the application layer ensure that there are sufficient checks
so one customer can't read another customers data


On Tue, Aug 5, 2014 at 9:09 AM, Phil Luckhurst <> wrote:

> Is there any mention of this limitation anywhere in the Cassandra
> documentation? I don't see it mentioned in the 'Anti-patterns in Cassandra'
> section of the DataStax 2.0 documentation or anywhere else.
> When starting out with Cassandra as a store for a multi-tenant application
> it seems very attractive to segregate data for each tenant using a tenant
> specific keyspace each with their own set of tables. It's not until you
> start browsing through forums such as this that you find out that it isn't
> going to scale above a few tenants.
> If you want to be able to segregate customer data in Cassandra is it the
> accepted practice to have multiple Cassandra installations?
> --
> View this message in context:
> Sent from the mailing list archive at

View raw message