The x8g.16xlarge pairs 64 vCPU with 1024 GiB of RAM, the 16.00 GiB-per-vCPU ratio that marks a memory-optimized instance. In the name, "x" is the extra-memory line, "8" is the generation, "g" marks AWS Graviton (ARM) processors and "16xlarge" is the size within the x8g family. It runs on AWS Graviton4 Processor at 2.7 GHz, and AWS introduced it in September 2024. x8g is the current generation of the x family, so there is no newer AWS size to migrate to. Spot's node ladder tops out below this size, so x8g.16xlarge becomes 8 × mh.vs1.2xlarge (128 vCPU, 1024 GiB combined), $6.25/hr on AWS in US East (N. Virginia), from $0.168/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 | $6.253 | $3.033 | $3.853 | $2.136 | $0.168 | $6.085 savings |
| US Central, Chicago | no AWS region | $0.168 | ||||
| US Central, Dallas | no AWS region | $1.048 | ||||
| Hong Kong | $0.168 | |||||
| Sydney, Australia | $7.503 | $1.071 | $4.624 | $2.563 | $0.168 | $7.335 savings |
| London, UK | $1.048 | |||||
| US West, San Jose | $0.015 | |||||
| US Central, Dallas 2 | no AWS region | $1.815 |