Amazon Elastic Compute Cloud
User Guide (API Version 2014-02-01)
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Instance Types

When you launch an instance, the instance type that you specify determines the hardware of the host computer used for your instance. Each instance type offers different compute, memory, and storage capabilities. Select an instance type based on the requirements of the application or software that you plan to run on your instance.

Amazon EC2 provides each instance with a consistent and predictable amount of CPU capacity, regardless of its underlying hardware.

Amazon EC2 dedicates some resources of the host computer, such as CPU, memory, and instance storage, to a particular instance. Amazon EC2 shares other resources of the host computer, such as the network and the disk subsystem, among instances. If each instance on a host computer tries to use as much of one of these shared resources as possible, each receives an equal share of that resource. However, when a resource is under-utilized, an instance can consume a higher share of that resource while it's available.

Each instance type provides higher or lower minimum performance from a shared resource. For example, instance types with high I/O performance have a larger allocation of shared resources. Allocating a larger share of shared resources also reduces the variance of I/O performance. For most applications, moderate I/O performance is more than enough. However, for applications that require greater or more consistent I/O performance, consider an instance type with higher I/O performance.

The maximum transmission unit (MTU) for an instance depends on its instance type. The following instance types provide 9001 MTU (jumbo frames): CC2, C3, R3, CG1, CR1, G2, HS1, HI1, I2, and M3. The other instance types provide 1500 MTU (Ethernet v2 frames).

To obtain additional, dedicated capacity for Amazon EBS I/O, you can launch some instance types as Amazon EBS-optimized instances. For more information, see Amazon EBS-Optimized Instances.

To optimize your instances for high performance computing (HPC) applications, you can launch some instance types in a placement group. For more information, see Placement Groups.

When you launch your instance, it uses one of two types of virtualization: paravirtual (PV) or hardware virtual machine (HVM). The virtualization type is determined by the AMI used to launch the instance; some instance types support both PV and HVM while others support only one or the other. HVM virtualization uses hardware-assist technology provided by the AWS platform. With HVM virtualization, the guest VM runs as if it were on a native hardware platform, except that it still uses PV network and storage drivers for improved performance.

Available Instance Types

Amazon EC2 provides the instance types listed in the following table.

Instance FamilyInstance Types

General purpose

m1.small | m1.medium | m1.large | m1.xlarge | m3.medium | m3.large | m3.xlarge | m3.2xlarge

Compute optimized

c1.medium | c1.xlarge | c3.large | c3.xlarge | c3.2xlarge | c3.4xlarge | c3.8xlarge | cc2.8xlarge

Memory optimized

m2.xlarge | m2.2xlarge | m2.4xlarge | r3.large | r3.xlarge | r3.2xlarge | r3.4xlarge | r3.8xlarge | cr1.8xlarge

Storage optimized

hi1.4xlarge | hs1.8xlarge | i2.xlarge | i2.2xlarge | i2.4xlarge | i2.8xlarge

Micro instances

t1.micro

GPU instances

cg1.4xlarge | g2.2xlarge

Hardware Specifications

For more information about the hardware specifications for each Amazon EC2 instance type, see Instance Type Details.

To determine which instance type best meets your needs, we recommend that you launch an instance and use your own benchmark application. Because you pay by the instance hour, it's convenient and inexpensive to test multiple instance types before making a decision. If your needs change, you can resize your instance later on. For more information, see Resizing Your Instance.