Amazon.com on Monday added more Web services to its EC2 cloud so customers can better manage the applications they send to run in the cloud.

CloudWatch will monitor the resources being used by an EC2 application. It provides visibility into CPU usage, disk reads and writes, and network traffic. With the metrics provided, the user can see operational performance and overall demand patterns as the application utilizes the resources it's been assigned, Peter DeSantis, general manager of EC2, said in a statement.

The tools start to aggregate and store operational data within minutes of an EC2 application startup, he said.

Auto Scaling will allow an EC2 customer to scale up an application, or scale it back down. By setting quality-of-service or response-time parameters, the EC2 user can ensure that the number of instances of a running application will scale up during demand spikes and back down as demand falls, said DeSantis. Auto Scaling is enabled by using CloudWatch. Paying fees for CloudWatch allows use of Auto Scaling, he said.

Elastic Load Balancing will allow an EC2 user to automatically distribute application traffic across multiple EC2 instances, so the workload never exceeds the available capacity and the application gains a measure of fault tolerance. Elastic Load Balancing recognizes when an application instance is underperforming, and routes traffic to healthy instances, until the unhealthy instances can be restored, said DeSantis.

CloudWatch and Elastic Load Balancing are available immediately on a pay-as-you-go basis. The new services improve the reliability of applications running in the cloud, Simon Plant, Capgemini's lead for cloud computing, said in the announcement. Capgemini is an IT consulting and outsourcing firm.

"Monitoring cloud assets, scaling capacity automatically, and balancing traffic efficiently has been among the most requested Amazon EC2 features," said DeSantis.

The Amazon move follows an earlier offering by the open source Web site management firm Hyperic, which announced a cloud application monitoring service for EC2 in November. Hyperic is now part of the open source company SpringSource.

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