QUEUE CREDIT MANAGEMENT

摘要

To prevent buffer overflow, a receiving entity may use credits to control the total amount of packets any single transmitting entity can forward. Once the assigned credits are spent, the transmitting entity cannot send data portions to the receiving entity until additional credits are provided. However, the logic in the receiving entity may be designed to manage a maximum number of credits that is less than the capacity of the buffer in the transmitting entity. For example, the receiving entity is designed to manage a maximum of eight credits but the buffer has room for twelve data portions. To use the buffer efficiently, the transmitting entity may identify when extra buffer storage is available and provide additional credits. In addition, the transmitting entity may control when the credits are provided such that the receiving entity is not allocated more credits that it was designed to manage.

主权项

1. A method comprising:
providing a number of credits to a first module not in excess of a maximum number of credits the first module is designed to manage, wherein the first module maintains a credit count that is decreased each time a data packet is transmitted from the first module to a second module; storing a plurality of received data packets from the first module in a memory buffer in the second module, the memory buffer having predefined memory locations dedicated to storing data packets received only from the first module, wherein the number of memory locations exceeds the maximum number of credits the first module is designed to manage; and upon determining that the credit count of the first module is less than the maximum number of credits and that there is available space in the memory locations, providing an extra credit to the first module, thereby increasing the credit count.