r4.8xlarge

Analysis

The r4.8xlarge is a memory optimized instance in the r4 series with 32 vCPUs and 244 GiB of memory on Intel Xeon E5-2686 v4 (Broadwell) (up to 2.3 GHz), which makes it memory-heavy at 7.62 GiB of memory per vCPU.

Running it in N. Virginia instead of São Paulo saves $1,717 a month per instance: $2.13/hour against $4.48/hour, a 111% spread.

On demand it costs $2.13/hour in US East (N. Virginia), $1,553 a month if left running, which puts it mid-table for memory optimized types at the 28th percentile per vCPU ($0.0665 per vCPU-hour) and the 47th percentile per GiB ($0.00872 per GiB-hour).

The newer r5.8xlarge on Intel Xeon Platinum 8175 is 5.3% cheaper at $2.02/hour, which makes the r4.8xlarge hard to justify for new deployments.

Looking beyond its own line, 12 of 41 current types with 32 vCPUs and similar memory are cheaper. The cheapest of those is the r6g.8xlarge on AWS Graviton2 at $1.61/hour.

It is size 5 of 6 in the r4 series. Stepping up to the r4.16xlarge gives 64 vCPUs and 488 GiB for $1,553 more a month. Dropping to the r4.4xlarge saves $777 a month.

Reserving it for a year with no upfront payment cuts the Linux rate to $1.34/hour, which beats on demand once it runs more than 63% of the time; three years brings it to $0.9158/hour, 57% below on demand. Windows Server roughly adds 69% to the bill at $3.60/hour, because the licence is charged per vCPU.