The x2iezn.12xlarge pairs 48 vCPU with 1536 GiB of RAM, the 32.00 GiB-per-vCPU ratio that marks a memory-optimized instance. In the name, "x" is the extra-memory line, "2" is the generation, "iezn" marks Intel processors, extended capacity, a higher clock and enhanced networking and "12xlarge" is the size within the x2iezn family. It runs on Intel Xeon Platinum 8252 at 4.5 GHz, and AWS introduced it in January 2022. AWS has since shipped x8i; x8i.12xlarge is the direct replacement at this size, scoring 1,197,605 CoreMark/s against this instance's 1,000,208 — roughly 20% more throughput for the same vCPU count. Spot's node ladder tops out below this size, so x2iezn.12xlarge becomes 11 × mh.vs1.2xlarge (176 vCPU, 1408 GiB combined), $10.01/hr on AWS in US East (N. Virginia), from $0.231/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.
Match qualityScale-out match
x2iezn.12xlarge gives you 48 vCPU and 1,536 GiB in a single machine. The largest comparable Spot node, mh.vs1.2xlarge, is 16 vCPU and 128 GiB, so the equivalent here is 11 nodes rather than one.
Spot runs as managed Kubernetes, so a 11-node pool is the normal way to run things rather than a workaround. If your workload already sits behind a load balancer, a queue or a scheduler, it spreads across them without changes. If it needs all 48 cores and 1,536 GiB in one process, it does not.
