Memory usage keeps growing

Hi,

I have been testing out our ElasticSearch implementation on a good sized EC2 instance running Ubuntu. It runs great even under high load, but I have noticed that as you continue to pound it with requests, the memory usage keeps growing until you swap everything and the box falls over. The server has 8GB of RAM and the data indexed only a couple hundred MB.

Any ideas or thoughts as to why this is occurring?

Thanks,
Justin