The r8a.48xlarge is a memory-optimized AWS EC2 instance: 192 vCPU and 1536 GiB of memory, 8.00 GiB per vCPU. In the name, "r" stands for RAM, "8" is the generation, "a" marks AMD processors and "48xlarge" is the size within the r8a family. It runs on AMD EPYC 9R45 Processor at Up to 4.5 GHz, and AWS introduced it in November 2025. AWS has since shipped r9g; r9g.48xlarge is the direct replacement at this size. No single Spot node covers 192 vCPU and 1536 GiB, so the equivalent is a fleet: 12 × mh.vs1.2xlarge, 192 vCPU and 1536 GiB in total, $15.34/hr on AWS in US East (N. Virginia), from $0.252/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 | $15.337 | $4.104 | $0.252 | $15.085 savings | ||
| US Central, Chicago | no AWS region | $0.252 | ||||
| US Central, Dallas | no AWS region | $1.572 | ||||
| Hong Kong | $0.252 | |||||
| Sydney, Australia | $0.252 | |||||
| London, UK | $1.572 | |||||
| US West, San Jose | $0.024 | |||||
| US Central, Dallas 2 | no AWS region | $2.904 |