The c8gn.16xlarge is a compute-optimized AWS EC2 instance: 64 vCPU and 128 GiB of memory, 2.00 GiB per vCPU. In the name, "c" stands for compute, "8" is the generation, "gn" marks AWS Graviton (ARM) processors and enhanced networking and "16xlarge" is the size within the c8gn family. It runs on AWS Graviton4 Processor at 2.8 GHz, and AWS introduced it in June 2025. AWS has since shipped c9g; c9g.16xlarge is the direct replacement at this size, scoring 2,295,964 CoreMark/s against this instance's 1,838,816 — roughly 25% more throughput for the same vCPU count. No single Spot node covers 64 vCPU and 128 GiB, so the equivalent is a fleet: 4 × ch.vs1.2xlarge, 64 vCPU and 128 GiB in total, $3.79/hr on AWS in US East (N. Virginia), from $0.164/hr on Rackspace Spot. Spot delivers compute as managed Kubernetes, so a node pool of that size is the native shape of the answer rather than a workaround — provided the workload scales horizontally.
| Region | AWS on-demand | AWS Spot | 1-yr Reserved | 3-yr Reserved | Rackspace Spot | You save |
|---|---|---|---|---|---|---|
| US East, N. Virginia | $3.792 | $0.902 | $0.164 | $3.628 savings | ||
| US Central, Chicago | no AWS region | $0.044 | ||||
| US Central, Dallas | no AWS region | $0.444 | ||||
| Hong Kong | $5.021 | $0.164 | $4.857 savings | |||
| Sydney, Australia | $4.951 | $1.266 | $0.164 | $4.787 savings | ||
| London, UK | $4.494 | $0.807 | $0.524 | $3.970 savings | ||
| US West, San Jose | $4.740 | $0.607 | $0.008 | $4.732 savings | ||
| US Central, Dallas 2 | no AWS region | $0.488 | ||||
| US East, N. Virginia 2 | $3.792 | $0.902 | $0.648 | $3.144 savings |