Specifies the maximum number of TCP segments received from directly connected destinations before an acknowledgment (ACK) is generated. TCP segments are measured in units of maximum segment size (MSS) for individual connections. If set to 0 or 1, it means no ACKs are delayed, assuming all segments are 1 MSS long. The actual number is dynamically calculated for each connection. The value is the default maximum.
0 to 16
Do not change the value. In some circumstances, when the network traffic becomes very bursty because of the delayed ACK effect, decrease the value. Do not decrease this value below 2.