Amazon EC2 C8i and C8i-flex Instances

Many customers do not fully utilize all the compute resources of an EC2 instance. Those customers are therefore paying for performance that they don’t need. Amazon EC2 C8i-flex instances offer the easiest way to achieve improved price performance for compute intensive workloads. Amazon EC2 Flex instances efficiently use compute resources with the ability to scale up to full compute performance majority of the time. Flex instances are purpose-built to optimize cost and performance.

C8i-flex instances offer the easiest way to optimize costs for compute intensive workloads. They deliver up to 15% better price performance compared to previous generation instances. C8i provides additional larger instance sizes, including two metal sizes, to run more demanding and larger-sized workloads.

C8i-flex offers the most common sizes from large to 16xlarge, while C8i provides sizes scaling up to 96xlarge (including metal sizes), with varying amounts of vCPU, memory, networking, and storage. This allows for larger data processing and improved scaling for caching workloads.

C8i and C8i-flex instances are built on the AWS Nitro System, a combination of dedicated hardware and lightweight hypervisor. These instances feature the latest sixth generation AWS Nitro Cards, which improve network throughput for workloads that handle small packets, such as web, application, and gaming servers. The new instances also support IBC feature, offering flexibility in allocating resources between network and Amazon Elastic Block Storage (Amazon EBS) bandwidth.

C8i and C8i-flex instances are powered by custom Intel Xeon 6 processors with a sustained all-core turbo frequency of 3.9 GHz. These custom processors offer the highest compute performance and fastest memory among comparable Intel processors in the cloud. Both instances include support for always-on memory encryption.

C8i and C8i-flex instances use DDR5 7200MT/s DIMMs, providing 2.5x higher memory throughput compared to previous generation instances. C8i-flex instances support up to 20 Gbps bandwidth to Amazon EBS and up to 30 gigabits per second (Gbps) of networking bandwidth. C8i instances support up to 80 Gbps bandwidth to Amazon EBS and up to 100 Gbps of networking bandwidth. C8i instances also support Elastic Fabric Adapter (EFA) in the 48xlarge, 96xlarge, metal-48xl, and metal-96xl instance sizes.

C8i and C8i-flex instances feature 4.6x larger L3 cache versus previous generation instances, significantly improving latency for CPU-based inference, scientific computing, and caching workloads. Intel Xeon 6 processors offer enhanced built-in accelerators such as Advanced Matrix Extensions (AMX) with FP16 support on C8i and C8i-flex instances, enabling a wider range of CPU-based inference workloads.

The AWS Nitro System is the foundation for our next generation of EC2, enabling AWS to innovate faster, further reduce cost for our customers, and deliver added benefits like increased security and new instance types. These instances are built using the latest sixth generation AWS Nitro Cards, which offload and accelerate I/O for functions, increasing overall system performance. The new Nitro cards deliver up to 2x more network and 2x more EBS bandwidth over comparable previous generation instances.

C8i and C8i-flex instances support a new instance bandwidth configuration feature that offers flexibility in allocating resources between network and EBS bandwidth. This allows customers to scale network or EBS bandwidth by 25% and improve database performance, query processing, and logging speeds