Cassandra resets connection under heavy insert workload
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I have a cassandra cluster of 8 nodes, cassandra 1.0.8. 

I'm trying to do lots of small inserts in a loop with batch_mutate(). After some time (~200K inserts) server resets connection with following exception:

    org.apache.thrift.transport.TTransportException: java.net.SocketException: Connection reset
	at org.apache.thrift.transport.TIOStreamTransport.write(TIOStreamTransport.java:147)
	at org.apache.thrift.transport.TFramedTransport.flush(TFramedTransport.java:157)
	at org.apache.cassandra.thrift.Cassandra$Client.send_batch_mutate(Cassandra.java:998)
	at org.apache.cassandra.thrift.Cassandra$Client.batch_mutate(Cassandra.java:986)
	at org.scale7.cassandra.pelops.Mutator$1.execute(Mutator.java:46)
	at org.scale7.cassandra.pelops.Mutator$1.execute(Mutator.java:42)
	at org.scale7.cassandra.pelops.Operand.tryOperation(Operand.java:56)
	at org.scale7.cassandra.pelops.Mutator.execute(Mutator.java:51)
        ...
        Caused by: java.net.SocketException: Connection reset
	at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:96)
	at java.net.SocketOutputStream.write(SocketOutputStream.java:136)
	at org.apache.thrift.transport.TIOStreamTransport.write(TIOStreamTransport.java:145)
	... 25 more

Otherwise than it, the cluster works fine. Server logs are clean. 

What might be causing this problem?

Thanks!