The r8idb.metal-48xl pairs 192 vCPU with 1536 GiB of RAM, the 8.00 GiB-per-vCPU ratio that marks a memory-optimized instance. In the name, "r" stands for RAM, "8" is the generation, "idb" marks Intel processors, local NVMe storage and block-storage optimisation and "metal-48xl" is the size within the r8idb family. It runs on Intel Xeon Scalable (Granite Rapids) at 3.9 GHz, and AWS introduced it in June 2026. AWS has since shipped r9g; r9g.metal-48xl is the direct replacement at this size. Spot's node ladder tops out below this size, so r8idb.metal-48xl becomes 12 × mh.vs1.2xlarge (192 vCPU, 1536 GiB combined), $22.51/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 | $22.509 | $5.209 | $0.252 | $22.257 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 |