C6a instances deliver up to 15% better price performance than C5a instances and 10% lower cost than comparable x86-based EC2 instances. C6a instances also offer new larger sizes with up to 192 vCPUs and 384 GiB of memory, enabling you to consolidate workloads on fewer instances and save on per core licensing costs.

C6a instances add to the broadest and deepest selection of EC2 instances in the cloud and provide customers 11 different instance sizes that feature varying amounts of vCPU, memory, networking, and storage. This enables customers to run a broad range of compute-intensive workloads.

C6a instances are built on the AWS Nitro System, a combination of dedicated hardware and lightweight hypervisor which delivers practically all of the compute and memory resources of the host hardware to your instances for better overall performance and security.

Amazon EC2 C6a instances are powered by 3rd generation AMD EPYC processors (code named Milan) with an all-core turbo frequency of 3.6 GHz and include support for AMD Transparent Single Key Memory Encryption (TSME), which encrypts data in physical memory. C6a instances support the new Advanced Vector Extension (AVX-2) instructions for faster execution of cryptographic algorithms. They also support AMD SEV-SNP. For more information about AMD SEV-SNP and pricing, refer to this documentation.

The largest size of C6a instances supports 40 Gbps bandwidth to Amazon Elastic Block Store (EBS), which is more than double that of C5a instances. C6a instances also support up to 50 Gbps networking, which is 2.5 times that of C5a instances. Customers can also enable Elastic Fabric Adapter (EFA) on the 48xlarge size of C6a.

The AWS Nitro System is a rich collection of building blocks that offloads many of the traditional virtualization functions to dedicated hardware and software to deliver high performance, high availability, and high security while also reducing virtualization overhead.