Overview and current status of the SKA-Low Monitoring, Control and Calibration Subsystem (MCCS)

SKA-Low is the low frequency radio telescope currently under construction in Western Australia. At its final extent, it will consist of 512 stations up to 74 km apart, each containing 256 antennas which can be used in different combinations to digitally “point” the telescope. The Monitoring, Control and Calibration Subsystem (MCCS) is responsible for performing calibration and providing local monitoring and control of all of the LFAA (Low Frequency Aperture Array) hardware components. This includes managing the allocation of resources for an observation, and the aggregation of health status. SKAO has adopted the Tango control system framework, and the MCCS software comprises upwards of 18 different Tango devices, some of which are replicated dozens of times for a single station. This complexity poses a significant challenge to computing resources and reliability when considering how to scale up the system, first to the 16 stations to be constructed and integrated by January 2026, then 68 stations at the end of 2026, and targeting 307 stations by mid-2028. This paper will describe the MCCS architecture, report on our latest performance profiling, and discuss how we are preparing for the AA 2 construction milestone which will need to support 68 stations.