Dynamic link width adjustment

摘要

Embodiments help dynamically configure the width of PCIe links and also determine how to best configure the appropriate link width. This helps avoid situations where PCIe links are almost always active even at very low traffic rates. Embodiments achieve these benefits based on, for example, run-time monitoring of bandwidth requirement for integrated and non-integrated ports located downstream for the PCIe controller. This provides power savings with little impact on performance. Other embodiments are discussed herein.

主权项

1. A method comprising:
coupling a downstream module, which includes a controller and a switch fabric, to an upstream module, which includes a host processor, via a link having a dynamically configurable width; initializing the controller; and after the controller has been initialized, the downstream module both determining an input/output (I/O) bandwidth for the downstream module and dynamically adjusting the width of the link based on the determination; wherein dynamically adjusting the width of the link comprises the downstream module immediately increasing, before a first time period transpires, the width of the link when the determined bandwidth is greater than the width of the link, and non-immediately decreasing the width of the link, after a second time period transpires, when the determined bandwidth is less than the width of the link; the second time period being longer than the first time period.