Arbitration allocating requests during backpressure

A method comprising:

• receiving a plurality of requests to access a destination from at least one source;
• granting a subset of the plurality of requests access to the destination during a first arbitration window;
• detecting an absence of backpressure at the destination based on a number of the plurality of requests available for receipt by the destination during the first arbitration window exceeding a number of requests included in the subset of the plurality of requests;
• assigning a masking value by decrementing an index value for a lookup table that specifies request limit values for the at least one source, the masking value decreasing the number of the plurality of requests;
• and
• granting an increased number of requests access to the destination during a second arbitration window based on the masking value.

A system comprising:

• a storage device including a lookup table that specifies request limit values;
• and
• hardware circuitry configured to:
• receive a plurality of requests to access a destination during a first arbitration window and grant access to each of the plurality of requests during the first arbitration window;
• detect backpressure at the destination during the first arbitration window based on a number of the plurality of requests exceeding a number of requests available for receipt by the destination during the first arbitration window;
• assign a masking value that reduces the number of the plurality of requests, in response to detecting backpressure at the destination during the first arbitration window, the masking value being assigned by updating an index value for the lookup table;
• and
• grant a limited number of requests access to the destination during a second arbitration window based on the masking value.