c7i.16xlarge

Analysis

The c7i.16xlarge is a compute optimized instance in the c7i series with 64 vCPUs and 128 GiB of memory on Intel Xeon Scalable (Sapphire Rapids) (up to 3.2 GHz), which makes it compute-heavy at 2 GiB of memory per vCPU.

Within the same generation and size, the c7g.16xlarge on AWS Graviton3 costs $2.32/hour, 19% less ($391 a month), though switching means rebuilding software for arm64. The other variants are the c7i-flex.16xlarge at $2.71, the c7gd.16xlarge at $2.90 and the c7a.16xlarge at $3.28.

Running it in Mumbai instead of São Paulo saves $1,128 a month per instance: $2.86/hour against $4.40/hour, a 54% spread.

Reserving it for a year with no upfront payment cuts the Linux rate to $1.89/hour, which beats on demand once it runs more than 66% of the time; three years brings it to $1.26/hour, 56% below on demand. Windows Server roughly doubles the bill at $5.80/hour, because the licence is charged per vCPU.

On demand it costs $2.86/hour in US East (N. Virginia), $2,085 a month if left running, which puts it mid-table for compute optimized types at the 40th percentile per vCPU ($0.0446 per vCPU-hour) and the 44th percentile per GiB ($0.0223 per GiB-hour).

Looking beyond its own line, 13 of 28 current types with 64 vCPUs and similar memory are cheaper. The cheapest of those is the hpc7g.16xlarge on AWS Graviton3 at $1.68/hour.