xprt_adjust_cwnd (9) Linux Manual Page
xprt_adjust_cwnd – adjust transport congestion window
Synopsis
void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result);Arguments
xprt
-
- pointer to xprt
task
- recently completed RPC request used to adjust window
result
- result code of completed RPC request
Description
The transport code maintains an estimate on the maximum number of out- standing RPC requests, using a smoothed version of the congestion avoidance implemented in 44BSD. This is basically the Van Jacobson congestion algorithm: If a retransmit occurs, the congestion window is halved; otherwise, it is incremented by 1/cwnd when
– a reply is received and – a full number of requests are outstanding and – the congestion window hasn’t been updated recently.