x8g.4xlarge

Analysis

The x8g.4xlarge is a memory optimized instance in the x8g series with 16 vCPUs and 256 GiB of memory on AWS Graviton4 (up to 2.7 GHz), which makes it very memory-heavy at 16 GiB of memory per vCPU.

Running it in N. Virginia instead of Frankfurt saves $454 a month per instance: $1.56/hour against $2.18/hour, a 40% spread. It is not offered in Canada Central, São Paulo, London, Mumbai, Singapore and Tokyo, so plan around that if you need a presence there.

It is the cheapest of the 2 processor variants AWS sells at this size and generation. The x8i.4xlarge on Intel Xeon Scalable (Granite Rapids) costs 12% more, and no others also sit above it.

On demand it costs $1.56/hour in US East (N. Virginia), $1,141 a month if left running, which puts it mid-table for memory optimized types at the 74th percentile per vCPU ($0.0977 per vCPU-hour) and the 3rd percentile per GiB ($0.00611 per GiB-hour).

Looking beyond its own line, 1 of 4 current types with 16 vCPUs and similar memory are cheaper. The cheapest of those is the x2gd.4xlarge on AWS Graviton2 at $1.34/hour.

Reserving it for a year with no upfront payment cuts the Linux rate to $0.9633/hour, which beats on demand once it runs more than 62% of the time; three years brings it to $0.5340/hour, 66% below on demand.