A method and system for regulating tasks of background processes so as to reduce interference with foreground processes. The progress rate of a background task (e.g., amount of work performed per unit time) is measured and evaluated against a target amount. If the progress rate appears degraded, the background task is suspended for a computed time interval so as to back off from its interference with a foreground process. Each time the progress rate appears degraded, the time interval is exponentially increased from its previous value up to a maximum, however if the performance appears normal, the time interval is reset to a minimum. Evaluation of the work is statistically based so as to eliminate variations in measurements, and automatic calibration of the target amount is provided, as is a mechanism for prioritizing multiple background tasks.