In many cases, scaling out (by launching additional instances) is the best way to bring additional CPU processing power and memory to bear on a problem, while also distributing network traffic across multiple NICs (Network Interface Controllers). Certain workloads, however, are better supported by scaling up with a more capacious instance. Examples of these workloads include commercial and open source relational databases, mid-tier caches such as memcache, and media rendering.
To enable further scaling up for these workloads, we are introducing a new family of memory-heavy EC2 instances with the Double and Quadruple Extra Large High-Memory instance types. Here are the specs (note that an ECU is an EC2 compute unit, equivalent in CPU power to a 1.0-1.2 GHz 2007-era AMD Opteron or Intel Xeon processor):
- Double Extra Large - 34.2 GB of RAM, and 13 ECU (4 virtual cores with 3.25 ECU each), 64-bit platform.
- Quadruple Extra Large - 68.4 GB of RAM, and 26 ECU (8 virtual cores with 3.25 ECU each), 64-bit platform.
These new instance types are available now in multiple Availability Zones of both EC2 regions (US and Europe). Double Extra Large instances cost $1.20 per instance hour and the Quadruple Extra Large instances cost $2.40 per instance hour (these prices are for Linux instances in the US region).
These new instances use the most recent generation of processor and platform architectures. In order to get the best possible performance you should experiment with compiler settings and may also want to check out specialized compilers such as Intel's Professional Edition and AMD's Open64 Compiler Suite. As with all EC2 instances where the processor architecture underlying the virtualized compute resources may vary, you may want to think about ways to detect and adapt to the processor type at launch time if this will make a difference for your particular workload.