Patent ID: 7840718

Claim:
A computer program product for processing communications between a control unit and a channel subsystem in an input/output processing system, comprising a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising: sending by the channel subsystem, a Process Log-in (PRLI) message to the control unit, the PRLI message comprising a maximum time for suspension of input/output operations that the channel subsystem can allow in an Initiation Delay Time field in a Process Log-out (PRLO) from the control unit; the channel subsystem receiving a Process Log-out (PRLO) message from the control unit, the message requesting suspension of input/output operations between the control unit and the channel subsystem for a period of time, the period of time being defined by the Initiation Delay Time field in the PRLO message; responsive to the PRLO message, suspending by the channel all input/output operation messages for the period of time, wherein suspending comprises stopping input/output operation messages during the period of time; and responsive to an expiration of the period of time, sending a Process Log-in (PRLI) message from the channel subsystem to the control unit to re-initiate an operating environment between the channel subsystem and the control unit.