c7i.12xlarge

Analysis

The c7i.12xlarge is a compute optimized instance in the c7i series with 48 vCPUs and 96 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.12xlarge on AWS Graviton3 costs $1.74/hour, 19% less ($293 a month), though switching means rebuilding software for arm64. The other variants are the c7i-flex.12xlarge at $2.03, the c7gd.12xlarge at $2.18 and the c7a.12xlarge at $2.46.

Running it in Mumbai instead of São Paulo saves $846 a month per instance: $2.14/hour against $3.30/hour, a 54% spread.

Reserving it for a year with no upfront payment cuts the Linux rate to $1.42/hour, which beats on demand once it runs more than 66% of the time; three years brings it to $0.9430/hour, 56% below on demand. Windows Server roughly doubles the bill at $4.35/hour, because the licence is charged per vCPU.

On demand it costs $2.14/hour in US East (N. Virginia), $1,564 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).

Compared with the previous generation, it costs 5.0% more than the c6i.12xlarge on Intel Xeon 8375C (Ice Lake) ($74.46 more a month per instance), in exchange for the newer processor. The newer c8i.12xlarge on Intel Xeon Scalable (Granite Rapids) is 5.0% dearer at $2.25/hour.