The r8idb.4xlarge is a memory-optimized AWS EC2 instance: 16 vCPU and 128 GiB of memory, 8.00 GiB per vCPU. In the name, "r" stands for RAM, "8" is the generation, "idb" marks Intel processors, local NVMe storage and block-storage optimisation and "4xlarge" is the size within the r8idb family. It runs on Intel Xeon Scalable (Granite Rapids) at 3.9 GHz, and AWS introduced it in May 2026. AWS has since shipped r9g; r9g.4xlarge is the direct replacement at this size. Rackspace Spot's mh.vs1.2xlarge is a like-for-like substitute at 16 vCPU and 128 GiB, $1.88/hr on AWS in US East (N. Virginia), from $0.021/hr on Rackspace Spot.
| Region | AWS on-demand | AWS Spot | 1-yr Reserved | 3-yr Reserved | Rackspace Spot | You save |
|---|---|---|---|---|---|---|
| US East, N. Virginia | $1.876 | $1.184 | $0.021 | $1.855 savings | ||
| US Central, Chicago | no AWS region | $0.021 | ||||
| US Central, Dallas | no AWS region | $0.131 | ||||
| Hong Kong | $0.021 | |||||
| Sydney, Australia | $0.021 | |||||
| London, UK | $0.131 | |||||
| US West, San Jose | $0.002 | |||||
| US Central, Dallas 2 | no AWS region | $0.242 |