The sections below outline the resources that the LoadMaster uses.

CPU

CPU indicates the processing power of an appliance. CPU is measured in cycles. These cycles represent the time utilized to process a piece of data. Depending on the model of LoadMaster, the processor may have multiple cores. This allows multiple processes to be performed simultaneously. However, this does not automatically double the processing power of a unit. Processes must be specifically designed to utilize multiple cores. Certain processes in the LoadMaster are multi-threaded while others are not. This can put constraints on certain processes within the LoadMaster.

RAM

RAM indicates the amount of memory available to a LoadMaster. This is primarily used to keep track of connections and persistence records. A certain amount is also consumed by the operating system. RAM can also be used for caching operations.

Network Load

Network load indicates the level of activity both on a particular interface and as a global value. All current LoadMaster models contain 10/100/1000 interfaces which can pass a maximum amount of 1Gbps. The other constraint on network load is the global throughput value. This value represents the maximum amount of network traffic which can be processed at a given time. Increases in network load have a consequence of driving up CPU utilization as each packet requires processing in order to determine what needs to be done with it.

Cavium TPS

On hardware LoadMaster models containing a Cavium SSL ASIC card, there is an additional metric to consider called Cavium TPS. An ASIC is an Application-Specific Integrated Circuit; this provides acceleration for SSL handshakes. This allows SSL offloading to be dramatically accelerated while also reducing CPU load versus comparable models without the ASIC. Each model has a limited SSL TPS which can be accomplished with the card. This will limit the amount of new SSL connections per second regardless of other metrics.