ACU
The concept of the Azure Compute Unit (ACU) encapsulates infomation about CPU performance in each Azure service which relies on CPU performance to classify its SKU plan. The basic reference for ACU is the Azure Standard_A1 (small) VM corresponding to 100 ACUs. All other Azure compute service SKUs advertise certain levels of ACU, which are multipliers of the reference Standard_A1 SKU with ACU=100. ACUs utilize the Intel Turbo and AMD Boost technologies to increase CPU frequency. Refer to Microsoft official ACU documentation at https://docs.microsoft.com/en-us/azure/virtual-machines/acu for more details.