--- nfs.c.orig	Tue Mar 12 21:44:19 2002
+++ nfs.c	Thu Mar 14 07:51:43 2002
@@ -321,6 +321,14 @@
 	int retries;
 	long *p;
 
+	static int tokens=0;
+	/*
+	 * Try to implement something similar to a window protocol in
+	 * terms of response to losses. On successful receive, increment
+	 * the number of tokens by 1 (cap at 256). On failure, halve it.
+	 * When the number of tokens is >= 2, use a very short timeout.
+	 */
+
 	id = rpc_id++;
 	buf.u.call.id = htonl(id);
 	buf.u.call.type = htonl(MSG_CALL);
@@ -336,9 +344,14 @@
 	*p++ = 0;		/* unused parameter */
 	for (retries = 0; retries < MAX_RPC_RETRIES; retries++) {
 		long timeout = rfc2131_sleep_interval(TIMEOUT, retries);
+		if (tokens >= 2)
+			timeout = TICKS_PER_SEC/2;
+
 		udp_transmit(arptable[server].ipaddr.s_addr, sport, port,
 			(char *)p - (char *)&buf, &buf);
 		if (await_reply(AWAIT_RPC, sport, &id, timeout)) {
+			if (tokens < 256)
+				tokens++;
 			rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
 			if (rpc->u.reply.rstatus || rpc->u.reply.verifier ||
 			    rpc->u.reply.astatus || rpc->u.reply.data[0]) {
@@ -355,7 +368,8 @@
 			} else {
 				return 0;
 			}
-		}
+		} else
+			tokens >>= 1;
 	}
 	return -1;
 }