Patent ID: 8032581

Claim:
A method, comprising: receiving, at a control unit, from a channel, a request to establish a relationship over a connection, wherein a first indicator associated with the request indicates that the relationship supports persistent information unit pacing across a plurality of command chains; sending, by the control unit, to the channel, a response indicating an acceptance of the relationship, wherein a second indicator associated with the response indicates whether the control unit supports persistent information unit pacing across the plurality of command chains; establishing the relationship and subsequent to establishing the relationship starting a first command chain; determining, by a channel, from the second indicator whether the control unit supports persistent information unit pacing across the plurality of commands chains; retaining, by the channel, an information unit pacing parameter value for a subsequent command chain to the first command chain, in response to determining by the channel that the second indicator indicates that the control unit supports persistent information unit pacing across the plurality of command chain, wherein the information unit pacing parameter value is set to a number that is different from a default value, wherein the default value is sixteen, and wherein the information unit pacing parameter value indicates the number of information units that are allowable to be in flight at any time for a command chain of the plurality of command chains; and avoiding retaining, by the channel, the information unit pacing parameter value for the subsequent command chain to the first command chain, in response to determining by the channel that the second indicator indicates that the control unit does not support persistent information unit pacing across the plurality of command chains.