Under certain circumstances it can be preferable to avoid re-sending TCP data to a peer service when data delivery has been delayed. Once data has been sent, and for which no acknowledgment has been received, the TCP retransmission timeout period represents a considerable delay. When the retransmission timeout (RTO) eventually expires it can be preferable not to retransmit the original data.
Onload can be configured to reset a TCP connection rather than attempt to retransmit data for which no acknowledgment has be received.
This feature is enabled with the EF_TCP_RST_DELAYED_CONN per stack environment variable and applies to all TCP connections in the onload stack. On any TCP connection in the onload stack, if the RTO timer expires before an ACK is received the TCP connection will be reset.