Cancel and replay protocol scheme to improve ordered bandwidth

A method comprising:

• sending a write request, without corresponding write data, to a coherent slave unit from an ordering master unit;
• starting a timer, by the ordering master unit, responsive to receiving an indication, from the coherent slave unit, that the write request is globally visible;
• cancelling the write request responsive to determining:
• the timer has expired;
• and
• at least one older write request is still not globally visible;
• and
• replaying the write request by resending the write request from the ordering master unit to the coherent slave unit responsive to cancelling the write request.

An apparatus comprising:

• an ordering master unit;
• and
• a coherent slave unit;
• wherein the apparatus is configured to:
• send a write request, without corresponding write data, to the coherent slave unit from the ordering master unit;
• start a timer, by the ordering master unit, responsive to receiving an indication, from the coherent slave unit, that the write request is globally visible;
• cancel the write request responsive to determining:
• the timer has expired;
• and
• at least one older write request is still not globally visible;
• and
• replay the write request by resending the write request from the ordering master unit to the coherent slave unit responsive to cancelling the write request.