Amazon announced today the availability of new instance types for EC2. Previously, EC2 instances were heavier on memory allocation than the new High-CPU instances. The new instance types, dubbed "High-CPU Instances" scale the processor count, or EC2 Compute Units, more quickly than memory. The proportion of CPU/memory in the High-CPU instances is considerably higher. Processor intensive applications that don't require substantial memory allocations can now be run on fewer instances, meaning they can be operated at a lower cost. Using the "Standard" instance types, the cost per EC2 Compute Unit (without respect to other factors) was $0.10/hour. The High-CPU Instance types cost only $0.04/hour to operate. Again, the rough pricing is subjective to the application's need for other resources such as RAM, disk space, I/O performance, and perhaps the advantage of running on a 64 bit platform. Keep this in mind when you compare the per-Compute Unit prices above.
Take a look at the instance types that were added:
| High CPU Medium Instance | |
| $0.20 / instance hour | |
| 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 | |
| $0.80 / instance hour | |
| 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 | |
Compare the "High-CPU Extra Large Instance" to the standard "Extra Large Instance" shown below:
| High CPU Medium Instance | |
| $0.20 / instance hour | |
| 15 GB memory | |
| 8 EC2 Compute Units (4 virtual cores with 2 EC2 Compute Units each) | |
| 1,690 GB instance storage | |
| 64-bit platform | |
| I/O Performance: High | |
Amazon defines a compute unit as follows (taken from here). Refer to Amazon's description of instance types for more details.
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.
Get some. :)
