The present invention extends to methods, systems, and computer program products for integrating external and cluster heat map data. Embodiments of the invention include a proxy service that manages (e.g., asynchronous) communication with cloud nodes. The proxy service simulates packets to on-premise services to simplify the integration with an existing heat map infrastructure. The proxy maintains a cache of performance counter mappings and timestamps on the on-premise head node to minimize the impact of latency into heat map infrastructure. In addition, data transfer is minimized by mapping a fixed set of resource based performance counters into a variable set of performance counters compatible with the on premise heat map infrastructure.