Could someone explain how the request/response queue function here? How do responses only reduce queue length?
ekr
When it says "responses" I think it refers to the act of taking the already computed response and sending it along the bus to the correct recipient, rather than the memory actually creating the response and placing it in the queue. In this sense, the response is already in the queue, and passing it along the bus to the correct processor can only reduce the queue length.
kayvonf
A request message is a message that is asking the receiver to do something. Like "send me the cache line containing address x". A request may trigger a response. A response does not result in additional messages on the interconnect. For example, a response message could a message containing be the bits of the requested cache line.
Could someone explain how the request/response queue function here? How do responses only reduce queue length?
When it says "responses" I think it refers to the act of taking the already computed response and sending it along the bus to the correct recipient, rather than the memory actually creating the response and placing it in the queue. In this sense, the response is already in the queue, and passing it along the bus to the correct processor can only reduce the queue length.
A request message is a message that is asking the receiver to do something. Like "send me the cache line containing address
x". A request may trigger a response. A response does not result in additional messages on the interconnect. For example, a response message could a message containing be the bits of the requested cache line.