Amazon Elastic Compute Cloud(EC2)

Amazon Elastic Compute Cloud, also known as "EC2", is a commercial web service which allows paying customers to rent computers on which to run their own computer applications. EC2 allows scalable deployment of applications by providing a web services interface through which customers can request an arbitrary number of Virtual Machines, i.e. server instances, on which they can load any software of their choice. Current users are able to create, launch, and terminate server instances on demand, hence the term "elastic". The Amazon implementation allows server instances to be created in zones that are insulated from correlated failures. EC2 is one of several Web Services provided by Amazon.com under the blanket term Amazon Web Services (AWS).

EC2 uses Xen virtualization. Each virtual machine, called an instance, is a virtual private server and can be one of three sizes; small, large or extra large. Instances are sized based on EC2 Compute Units which is the equivalent CPU capacity of physical hardware.

One EC2 Compute Unit equals 1.0-1.2 GHz 2007 Opteron or 2007 Xeon processor. The three available Instance sizes are sized as follows:

Small Instance

The small instance (default) is the "equivalent of a system with 1.7 GB of memory, 1 EC2 Compute Unit (1 virtual core with 1 EC2 Compute Unit), 160 GB of instance storage, 32-bit platform "

Large Instance

The large instance is the "equivalent of a system with 7.5 GB of memory, 4 EC2 Compute Units (2 virtual cores with 2 EC2 Compute Units each), 850 GB of instance storage, 64-bit platform".

Extra Large Instance

The extra large instance is the "equivalent of a system with 15 GB of memory, 8 EC2 Compute Units (4 virtual cores with 2 EC2 Compute Units each), 1690 GB of instance storage, 64-bit platform."

High-CPU Instances

Instances of this family have proportionally more CPU resources than memory (RAM) and are well suited for compute-intensive applications.

High-CPU Medium Instance Instances of this family have the following configuration:

           1.7 GB of memory
         5 EC2 Compute Units (2 virtual cores with 2.5 EC2 Compute Units each)
         350 GB of instance storage
         32-bit platform
         I/O Performance: Moderate

High-CPU Extra Large Instance Instances of this family have the following configuration:

           7 GB of memory
         20 EC2 Compute Units (8 virtual cores with 2.5 EC2 Compute Units each)
         1690 GB of instance storage
         64-bit platform
         I/O Performance: High