m7g.4xlarge is AWS's general-purpose EC2 size at 16 vCPU and 64 GiB. In the name, "m" is the general-purpose line, "7" is the generation, "g" marks AWS Graviton (ARM) processors and "4xlarge" is the size within the m7g family. It runs on AWS Graviton3 Processor at 2.5 GHz, and AWS introduced it in February 2023. AWS has since shipped m8g and m9g; m8g.4xlarge is the direct replacement at this size, scoring 511,100 CoreMark/s against this instance's 411,602 — roughly 24% more throughput for the same vCPU count. On Rackspace Spot the same shape is gp.vs2.2xlarge — 16 vCPU, 64 GiB, matched on both dimensions, about 94% below the US East (N. Virginia) on-demand rate.
Match qualityx86 substitution
m7g.4xlarge is Graviton (arm64). Rackspace Spot does not have arm64 servers, so gp.vs2.2xlarge is an x86_64 substitute with similar specs.
You will need x86 builds of your container images. Most software rebuilds without changes, but anything with compiled native code needs a real rebuild rather than a retag. Speed per core also differs between the two chips, so it is worth testing before deciding how many nodes to run.
