Image Number 3 for United States Patent #6038620.
A method and system in accordance with the present invention provides a mechanism that would dynamically change the backing factor. The backing factor is the amount of time needed to ensure that the I/O interface can stay ahead of the host interface. A method and system for providing a high performance control unit to provide for optimal matching of first and second interfaces comprises calculating a backing factor based upon minimal memory contention, optimal data rate and minimal rotational delay, and determining whether a particular result has been achieved. The method and system further includes calculating a new backing factor based upon current and projected data rates if the desired result has not been achieved. In a preferred embodiment, the initial backing factor is calculated assuming no memory contention, the best possible data rate for both the I/O and host interface and no rotational delay. This backing factor time is a smaller time unit than the static backing factor time of the conventional system, which was based on an average data rate.