ACU – Azure’s metric for comparing compute performance across VM series.
ACU is Azure’s way of comparing compute performance across different VM series. One ACU is roughly equivalent to the compute capacity of a small (Standard_A1) VM. Azure uses ACUs to help customers understand the relative compute performance between different VM series and make informed decisions about VM selection. ACUs consider CPU performance, memory bandwidth, and other factors. Different VM series offer different ACU ratings, with newer generations typically providing better performance per ACU. This metric is particularly useful when migrating workloads between different VM series or sizing new deployments.
