AWS EC2 Instances Type

General Purpose Instances

General Purpose instances

 provide customers with a balanced set of resources and a high level of processing performance on a low cost platform. Instances in this family are ideal for applications that require balanced CPU and memory performance. Examples of applications that will benefit from the performance of General Purpose instances include encoding, high traffic content management systems, and memcached.

• m3.medium: 3.75 GiB of memory, 1 vCPU, 3 EC2 Compute Units, 4 GB of SSD-based local instance storage, 64-bit platform
• m3.large: 7.5 GiB of memory, 2 VCPUs, 6.5 EC2 Compute Units, 32 GB of SSD-based local instance storage, 64-bit platform
• m3.xlarge: 15 GiB of memory, 4 vCPUs, 13 EC2 Compute Units, 80 GB of SSD-based local instance storage, 64-bit platform
• m3.2xlarge: 30 GiB of memory, 8 vCPUs, 26 EC2 Compute Units, 160 GB of SSD-based local instance storage, 64-bit platform

Compute Optimized Instances 

Compute Optimized Instance.

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

C4 instances are based on the Intel Xeon E5-2666 v3 ("Haswell") processor, and are designed to deliver the highest level of compute performance on Amazon EC2.

• c4.large: 3.75 GiB of memory, 2 vCPUs, 64-bit platform
• c4.xlarge: 7.5 GiB of memory, 4 vCPUs, 64-bit platform
• c4.2xlarge: 15 GiB of memory, 8 vCPUs, 64-bit platform
• c4.4xlarge: 30 GiB of memory, 16 vCPUs, 64-bit platform
• c4.8xlarge: 60 GiB of memory, 36 vCPUs, 64-bit platform
  

C3 instances are based on high frequency Intel Xeon E5-2680 v2 ("Ivy Bridge") processors, and are designed for running compute-intensive applications.

• c3.large: 3.75 GiB of memory, 2 vCPUs, 32 GB of SSD-based local instance storage, 64-bit platform
• c3.xlarge: 7.5 GiB of memory, 4 vCPUs, 80 GB of SSD-based local instance storage, 64-bit platform
• c3.2xlarge: 15 GiB of memory, 8 vCPUs, 160 GB of SSD-based local instance storage, 64-bit platform
• c3.4xlarge: 30 GiB of memory, 16 vCPUs, 320 GB of SSD-based local instance storage, 64-bit platform
• c3.8xlarge: 60 GiB of memory, 32 vCPUs, 640 GB of SSD-based local instance storage, 64-bit platform

Storage Optimized Instances

Instances of this family provide very high disk I/O performance or proportionally higher storage density per instance, and are ideally suited for applications that benefit from high sequential I/O performance across very large data sets. Storage-optimized instances also provide high levels of CPU, memory and network performance.

• i2.xlarge: 30.5 GiB of memory, 4 vCPUs, 800 GB of SSD-based instance storage, 64-bit platform
• i2.2xlarge: 61 GiB of memory, 8 vCPUs, 2 x 800 GB of SSD-based instance storage, 64-bit platform
• i2.4xlarge: 122 GiB of memory, 16 vCPUs, 4 x 800 GB of SSD-based instance storage, 64-bit platform
• i2.8xlarge: 244 GiB of memory, 32 vCPUs, 8 x 800 GB of SSD-based instance storage, 64-bit platform, 10 Gigabit Ethernet

Micro Instances 

Micro instances (t1.micro) 

provide a small amount of consistent CPU resources and allow you to increase CPU capacity in short bursts when additional cycles are available. They are well suited for lower throughput applications and web sites that require additional compute cycles periodically. You can learn more about how you can use Micro instances and appropriate applications in the Amazon EC2 documentation.

• t1.micro: (Default) 613 MiB of memory, up to 2 ECUs (for short periodic bursts), EBS storage only, 32-bit or 64-bit platform
  

EC2 Compute Unit (ECU) – One EC2 Compute Unit (ECU) provides the equivalent CPU capacity of a 1.0-1.2 GHz 2007 Opteron or 2007 Xeon processor.