r8idn.4xlarge

Analysis

The r8idn.4xlarge is a memory optimized instance in the r8idn series with 16 vCPUs and 128 GiB of memory on Intel Xeon Scalable (Granite Rapids) (up to 3.9 GHz), which makes it memory-heavy at 8 GiB of memory per vCPU.

Within the same generation and size, the r8g.4xlarge on AWS Graviton4 costs $0.9426/hour, 50% less ($681 a month), though switching means rebuilding software for arm64. The other variants are the r8i-flex.4xlarge at $1.06, the r8i.4xlarge at $1.11 and the r8gd.4xlarge at $1.18.

Running it in N. Virginia instead of Tokyo saves $295 a month per instance: $1.88/hour against $2.28/hour, a 22% spread. It is not offered in Canada Central, São Paulo, London, Mumbai, Singapore and Sydney, so plan around that if you need a presence there.

Per vCPU it is one of the dearer memory optimized types: 89% of the 385 current types in the family cost less than its $0.1172 per vCPU-hour. The premium mostly pays for the local NVMe disk. On demand it is $1.88/hour in US East (N. Virginia), or $1,369 for a 730-hour month.

Looking beyond its own line, 38 of 42 current types with 16 vCPUs and similar memory are cheaper. The cheapest of those is the r6g.4xlarge on AWS Graviton2 at $0.8064/hour.