c4.2xlarge

Analysis

The c4.2xlarge is a compute optimized instance in the c4 series with 8 vCPUs and 15 GiB of memory on Intel Xeon E5-2666 v3 (Haswell) (up to 2.9 GHz), which makes it compute-heavy at 1.88 GiB of memory per vCPU.

The newer c5.2xlarge on Intel Xeon Platinum 8124M is 15% cheaper at $0.3400/hour, which makes the c4.2xlarge hard to justify for new deployments.

It is size 3 of 5 in the c4 series. Stepping up to the c4.4xlarge gives 16 vCPUs and 30 GiB for $291 more a month. Dropping to the c4.xlarge saves $145 a month. Unit price is not flat across the series ($0.0442 to $0.0500 per vCPU-hour), so the size changes the rate you pay.

Running it in N. Virginia instead of São Paulo saves $161 a month per instance: $0.3980/hour against $0.6180/hour, a 55% spread.

Reserving it for a year with no upfront payment cuts the Linux rate to $0.2520/hour, which beats on demand once it runs more than 63% of the time; three years brings it to $0.1770/hour, 56% below on demand. Windows Server roughly doubles the bill at $0.7660/hour, because the licence is charged per vCPU.

On demand it costs $0.3980/hour in US East (N. Virginia), $291 a month if left running, which puts it mid-table for compute optimized types at the 55th percentile per vCPU ($0.0498 per vCPU-hour) and the 66th percentile per GiB ($0.0265 per GiB-hour).