c5a.8xlarge is AWS's compute-optimized EC2 size at 32 vCPU and 64 GiB. In the name, "c" stands for compute, "5" is the generation, "a" marks AMD processors and "8xlarge" is the size within the c5a family. It runs on AMD EPYC 7R32 at 3.3 GHz, and AWS introduced it in June 2020. AWS has since shipped c6a, c7a, c8a and c9g; c6a.8xlarge is the direct replacement at this size, scoring 624,969 CoreMark/s against this instance's 587,156 — roughly 6% more throughput for the same vCPU count. The closest Spot shape is ch.vs1.2xlarge at 16 vCPU, so this instance maps to 2 of them — 32 vCPU and 64 GiB across the fleet, about 93% below the US East (N. Virginia) on-demand rate. 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
c5a.8xlarge gives you 32 vCPU and 64 GiB in a single machine. The largest comparable Spot node, ch.vs1.2xlarge, is 16 vCPU and 32 GiB, so the equivalent here is 2 nodes rather than one.
Spot runs as managed Kubernetes, so a 2-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 32 cores and 64 GiB in one process, it does not.