An apparatus comprising: memory buffer logic to: identify a plurality of completed writes to memory, wherein the plurality of completed writes are to correspond to a plurality of write requests from a host device received over a buffered memory interface, and each of the plurality of write requests has a corresponding transaction identifier; and send a completion packet (1705, 1800) to the host device, wherein the completion packet (1705, 1800) is to comprise a plurality of completion fields, at least a subset of the plurality of completion fields are to be encoded with a respective one of a plurality of write completions to correspond to the plurality of completed writes, the completion packet is to further comprise a completion count field to indicate an amount of completion fields corresponding to the plurality of write completions, the completion packet is to be further encoded with the transaction identifiers corresponding to each of the plurality of write completions, the completion packet comprises a single link layer flow control unit, flit, and the flit is a multi-slot flit; wherein the multi-slot flit comprises at least three slots, two or more of the plurality of completion fields are to be included in a first one of the at least three slots, and two or more of the plurality of completion fields are to be included in a second one of the at least three slots, and at least one of the at least three slots is to be left unused.. memory buffer logic to: identify a plurality of completed writes to memory, wherein the plurality of completed writes are to correspond to a plurality of write requests from a host device received over a buffered memory interface, and each of the plurality of write requests has a corresponding transaction identifier; and send a completion packet (1705, 1800) to the host device, wherein the completion packet (1705, 1800) is to comprise a plurality of completion fields, at least a subset of the plurality of completion fields are to be encoded with a respective one of a plurality of write completions to correspond to the plurality of completed writes, the completion packet is to further comprise a completion count field to indicate an amount of completion fields corresponding to the plurality of write completions, the completion packet is to be further encoded with the transaction identifiers corresponding to each of the plurality of write completions, the completion packet comprises a single link layer flow control unit, flit, and the flit is a multi-slot flit; identify a plurality of completed writes to memory, wherein the plurality of completed writes are to correspond to a plurality of write requests from a host device received over a buffered memory interface, and each of the plurality of write requests has a corresponding transaction identifier; and send a completion packet (1705, 1800) to the host device, wherein the completion packet (1705, 1800) is to comprise a plurality of completion fields, at least a subset of the plurality of completion fields are to be encoded with a respective one of a plurality of write completions to correspond to the plurality of completed writes, the completion packet is to further comprise a completion count field to indicate an amount of completion fields corresponding to the plurality of write completions, the completion packet is to be further encoded with the transaction identifiers corresponding to each of the plurality of write completions, the completion packet comprises a single link layer flow control unit, flit, and the flit is a multi-slot flit; wherein the multi-slot flit comprises at least three slots, two or more of the plurality of completion fields are to be included in a first one of the at least three slots, and two or more of the plurality of completion fields are to be included in a second one of the at least three slots, and at least one of the at least three slots is to be left unused..