Avaya Aura® MS detects the number of logical processors and available system memory on each restart and adjusts its internal buffer pools and scalability limits accordingly. This is achieved by selecting a capacity profile (also known as a scalability profile) that best suites the underlying physical or virtual hardware. This scalability profile feature helps conserve memory and processing overhead on servers with less than optimal memory or processor configurations. It essentially avoids wasting processor cycles and memory by allocating critical thread counts to match the number of logical processors and sizing the server's data structures and buffer pools to match the available memory.

The currently selected capacity profile is visible on the Avaya Aura® MS Element Manager on the server profile page, along with the maximum sessions that the server can support in this configuration. An MPU rating estimate is also provided. Note that labels are assigned to each distinct capacity profile. Currently there are five profiles: tiny, small, medium, large, extra-large. These profiles are applicable to both bare metal and virtualized servers. The profile ranges and constraints have changed in Avaya Aura® MS 7.8 compared to 7.7.

The capacity profile range starts at 300 concurrent sessions at the lowest end and tops out at 5000 (the media session limit is still 4000 sessions; the 5000 number includes control channels). It is important to note that the capacity profile selected is not an estimate of maximum capacity (it is designed to error on the side of large), although it does represent a hard limit on the maximum number of concurrent sessions. The capacity profile is designed to be estimated higher than the maximum media processing capacity to leave room for control channels, and to leave room for very high-performance machines.

For example, the Media Server Profile 1 (4 vCPU small OVA) uses the small capacity profile. The theoretical maximum number of sessions including control channels is 1000. The MPU rating remains at 550 for this OVA configuration in all cases. This number does not imply the server has 1000 MPU. A quad core bare metal server with 4GB of ram will also select a small capacity profile

Note that although the minimum amount of RAM present to install Avaya Aura® MS is 2GB, this is not enough to reach top end capacity. At least 8GB of memory must be installed to support maximum capacity. Higher if other resources are utilized beyond audio processing.

*Avaya Aura® MS will not install without at least two logical processors present and 2GB of ram installed. Avaya Aura® MS does provide some variance/forgiveness in available RAM if it’s close to the minimum.