Cassandra Connection Pool

[Tristan Tarrant <tr...@gmail.com>]

Dear all,

first of all let me introduce myself (or rather what I do). I am the
developer of the Infinispan Cassandra CacheStore (
http://community.jboss.org/wiki/CassandraCacheStore) which allows
persistence of Infinispan's cache to Cassandra's keyspaces. While developing
the cachestore I needed a connection pool for managing thrift connections.
Since none existed (apart from the ones developed within projects such as
Hector, Pelops and Lucandra), I decided to take Filip Hanik's excellent
jdbc-pool (http://people.apache.org/~fhanik/jdbc-pool/jdbc-pool.html) and
"port" it to Cassandra.
During the development of the connection pool I had two needs which I solved
locally:

   - split the org.apache.cassandra.thrift class hierarchy from
   apache-cassandra-0.x.y.jar into a apache-cassandra-thrift-0.x.y.jar
   - have a standard org.apache.cassandra.thrift.CassandraDataSource
   interface, which I have defined as:

package org.apache.cassandra.thrift;

import org.apache.cassandra.thrift.Cassandra;
import org.apache.thrift.TException;

public interface CassandraThriftDataSource {
	Cassandra.Client getConnection() throws TException;
	void releaseConnection(Cassandra.Client connection);
}


In alternative a close() method on the Cassandra.Client interface,
which could be overridden to return the connection to the pool instead
of directly closing the underlying transport, although I believe this
might require changes to thrift.
This would provide a standard method for all client libraries to
obtain and release a connection (via a library, via JNDI, etc).

Would a patch against head be well accepted ?

Thanks for any suggestions

Tristan

Re: Cassandra Connection Pool

[Eric Evans <ee...@rackspace.com>]

On Tue, 2010-10-26 at 16:54 +0200, Tristan Tarrant wrote:
> I have a couple of questions:
> 
> - should the org.apache.cassandra.thrift classes still be included in
> the main jar ? Maybe just the ones compiled from src/java ?

I think it's OK to have the main jar depend on the thrift one. And, we
should just stick with what's in interface/thrift/gen-java for a thrift
jar since nothing under src/java is useful to a client.

> - should I also do the same for the avro client classes ? 

Yeah, sure.

-- 
Eric Evans
eevans@rackspace.com

Re: Cassandra Connection Pool

[Tristan Tarrant <tr...@gmail.com>]

On Tue, Oct 26, 2010 at 16:36, Eric Evans <ee...@rackspace.com> wrote:

>
> Sure, can you submit a ticket an attach the patch there?
>
> https://issues.apache.org/jira/browse/CASSANDRA


Hi Eric,

I have a couple of questions:

- should the org.apache.cassandra.thrift classes still be included in the
main jar ? Maybe just the ones compiled from src/java ?
- should I also do the same for the avro client classes ?

Tristan

Re: Cassandra Connection Pool

[Eric Evans <ee...@rackspace.com>]

On Tue, 2010-10-26 at 16:22 +0200, Tristan Tarrant wrote:
> first of all let me introduce myself (or rather what I do). I am the
> developer of the Infinispan Cassandra CacheStore (
> http://community.jboss.org/wiki/CassandraCacheStore) which allows
> persistence of Infinispan's cache to Cassandra's keyspaces. While
> developing the cachestore I needed a connection pool for managing
> thrift connections. Since none existed (apart from the ones developed
> within projects such as Hector, Pelops and Lucandra), I decided to
> take Filip Hanik's excellent jdbc-pool
> (http://people.apache.org/~fhanik/jdbc-pool/jdbc-pool.html) and
> "port" it to Cassandra.

[ ... ]

> Would a patch against head be well accepted ? 

Sure, can you submit a ticket an attach the patch there?

https://issues.apache.org/jira/browse/CASSANDRA

Thanks!

-- 
Eric Evans
eevans@rackspace.com