The i4g.large is a storage-optimized AWS EC2 instance: 2 vCPU and 16 GiB of memory, 8.00 GiB per vCPU. In the name, "i" is I/O, meaning local storage, "4" is the generation, "g" marks AWS Graviton (ARM) processors and "large" is the size within the i4g family. It runs on AWS Graviton2 Processor at 2.5 GHz, and AWS introduced it in May 2023. AWS has since shipped i7i and i8g; i7i.large is the direct replacement at this size, scoring 48,532 CoreMark/s against this instance's 37,845 — roughly 28% more throughput for the same vCPU count. Rackspace Spot's mh.vs1.medium is a like-for-like substitute at 2 vCPU and 16 GiB, about 93% below the US East (N. Virginia) on-demand rate.
Match qualityx86 substitution
i4g.large is Graviton (arm64). Rackspace Spot does not have arm64 servers, so mh.vs1.medium 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.
No local diski4g.large comes with 1 × 468 GB NVMe SSD attached to the machine. Spot nodes use network storage only, so that disk doesn't come with it. If you were using it as fast scratch space, you'd move to a persistent volume or object storage, which are slower to read.
