Parse anything in the stratum socket if it's full without waiting. Empty the socket even if a connection is not needed in case there are share returns.

cgminer.c

@@ -4643,7 +4643,7 @@ static void *stratum_thread(void *userdata)
 		/* Check to see whether we need to maintain this connection
 		 * indefinitely or just bring it up when we switch to this
 		 * pool */
-		if (!cnx_needed(pool)) {
+		if (!sock_full(pool, false) && !cnx_needed(pool)) {
 			suspend_stratum(pool);
 			clear_stratum_shares(pool);
 			clear_pool_work(pool);
@@ -4668,7 +4668,7 @@ static void *stratum_thread(void *userdata)
 		 * every minute so if we fail to receive any for 90 seconds we
 		 * assume the connection has been dropped and treat this pool
 		 * as dead */
-		if (unlikely(select(pool->sock + 1, &rd, NULL, NULL, &timeout) < 1))
+		if (!sock_full(pool, false) && select(pool->sock + 1, &rd, NULL, NULL, &timeout) < 1)
 			s = NULL;
 		else
 			s = recv_line(pool);

util.c

@@ -930,7 +930,7 @@ bool stratum_send(struct pool *pool, char *s, ssize_t len)
 }
 
 /* Check to see if Santa's been good to you */
-static bool sock_full(struct pool *pool, bool wait)
+bool sock_full(struct pool *pool, bool wait)
 {
 	SOCKETTYPE sock = pool->sock;
 	struct timeval timeout;

util.h

@@ -46,6 +46,7 @@ struct pool;
 enum dev_reason;
 struct cgpu_info;
 bool stratum_send(struct pool *pool, char *s, ssize_t len);
+bool sock_full(struct pool *pool, bool wait);
 char *recv_line(struct pool *pool);
 bool parse_method(struct pool *pool, char *s);
 bool extract_sockaddr(struct pool *pool, char *url);