Remove unused backoff code that doesn't do any good.

server-client.c

@@ -561,50 +561,6 @@ server_client_check_exit(struct client *c)
 	c->flags &= ~CLIENT_EXIT;
 }
 
-/*
- * Check if the client should backoff. During backoff, data from external
- * programs is not written to the terminal. When the existing data drains, the
- * client is redrawn.
- *
- * There are two backoff phases - both the tty and client have backoff flags -
- * the first to allow existing data to drain and the latter to ensure backoff
- * is disabled until the redraw has finished and prevent the redraw triggering
- * another backoff.
- */
-void
-server_client_check_backoff(struct client *c)
-{
-	struct tty	*tty = &c->tty;
-	size_t		 used;
-
-	used = EVBUFFER_LENGTH(tty->event->output);
-
-	/*
-	 * If in the second backoff phase (redrawing), don't check backoff
-	 * until the redraw has completed (or enough of it to drop below the
-	 * backoff threshold).
-	 */
-	if (c->flags & CLIENT_BACKOFF) {
-		if (used > BACKOFF_THRESHOLD)
-			return;
-		c->flags &= ~CLIENT_BACKOFF;
-		return;
-	}
-
-	/* Once drained, allow data through again and schedule redraw. */
-	if (tty->flags & TTY_BACKOFF) {
-		if (used != 0)
-			return;
-		tty->flags &= ~TTY_BACKOFF;
-		c->flags |= (CLIENT_BACKOFF|CLIENT_REDRAWWINDOW|CLIENT_STATUS);
-		return;
-	}
-
-	/* If too much data, start backoff. */
-	if (used > BACKOFF_THRESHOLD)
-		tty->flags |= TTY_BACKOFF;
-}
-
 /* Check for client redraws. */
 void
 server_client_check_redraw(struct client *c)

tmux.h

@@ -1168,8 +1168,7 @@ struct client {
 #define CLIENT_DEAD 0x200
 #define CLIENT_BORDERS 0x400
 #define CLIENT_READONLY 0x800
-#define CLIENT_BACKOFF 0x1000
+#define CLIENT_REDRAWWINDOW 0x1000
-#define CLIENT_REDRAWWINDOW 0x2000
 	int		 flags;
 
 	struct event	 identify_timer;