diff --git a/src/channel.c b/src/channel.c
index d2453322..8d6fb0ab 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -1734,6 +1734,9 @@ libssh2_channel_handle_extended_data(LIBSSH2_CHANNEL *channel,
  * It is important to not return 0 until the currently read channel is
  * complete. If we read stuff from the wire but it was no payload data to fill
  * in the buffer with, we MUST make sure to return LIBSSH2_ERROR_EAGAIN.
+ *
+ * The receive window must be maintained (enlarged) by the user of this
+ * function.
  */
 ssize_t _libssh2_channel_read(LIBSSH2_CHANNEL *channel, int stream_id,
                               char *buf, size_t buflen)
@@ -1755,15 +1758,6 @@ ssize_t _libssh2_channel_read(LIBSSH2_CHANNEL *channel, int stream_id,
         channel->read_state = libssh2_NB_state_created;
     }
 
-    /*
-     * =============================== NOTE ===============================
-     * I know this is very ugly and not a really good use of "goto", but
-     * this case statement would be even uglier to do it any other way
-     */
-    if (channel->read_state == libssh2_NB_state_jump1) {
-        goto channel_read_window_adjust;
-    }
-
     rc = 1; /* set to >0 to let the while loop start */
 
     /* Process all pending incoming packets in all states in order to "even
@@ -1872,26 +1866,6 @@ ssize_t _libssh2_channel_read(LIBSSH2_CHANNEL *channel, int stream_id,
            more off the network again */
         channel->read_state = libssh2_NB_state_created;
 
-    if(channel->remote.window_size < (LIBSSH2_CHANNEL_WINDOW_DEFAULT*30)) {
-        /* the window is getting too narrow, expand it! */
-
-      channel_read_window_adjust:
-        channel->read_state = libssh2_NB_state_jump1;
-        /* the actual window adjusting may not finish so we need to deal with
-           this special state here */
-        rc = _libssh2_channel_receive_window_adjust(channel,
-                                                    (LIBSSH2_CHANNEL_WINDOW_DEFAULT*60), 0, NULL);
-        if (rc)
-            return rc;
-
-        _libssh2_debug(session, LIBSSH2_TRACE_CONN,
-                       "channel_read() filled %d adjusted %d",
-                       bytes_read, buflen);
-        /* continue in 'created' state to drain the already read packages
-           first before starting to empty the socket further */
-        channel->read_state = libssh2_NB_state_created;
-    }
-
     return bytes_read;
 }
 
@@ -1904,16 +1878,29 @@ ssize_t _libssh2_channel_read(LIBSSH2_CHANNEL *channel, int stream_id,
  * currently read channel is complete. If we read stuff from the wire but it
  * was no payload data to fill in the buffer with, we MUST make sure to return
  * LIBSSH2_ERROR_EAGAIN.
+ *
+ * This function will first make sure there's a receive window enough to
+ * receive a full buffer's wort of contents. An application may choose to
+ * adjust the receive window more to increase transfer performance.
  */
 LIBSSH2_API ssize_t
 libssh2_channel_read_ex(LIBSSH2_CHANNEL *channel, int stream_id, char *buf,
                         size_t buflen)
 {
     int rc;
+    unsigned long recv_window;
 
     if(!channel)
         return LIBSSH2_ERROR_BAD_USE;
 
+    recv_window = libssh2_channel_window_read_ex(channel, NULL, NULL);
+
+    if(buflen > recv_window) {
+        BLOCK_ADJUST(rc, channel->session,
+                     _libssh2_channel_receive_window_adjust(channel, buflen,
+                                                            0, NULL));
+    }
+
     BLOCK_ADJUST(rc, channel->session,
                  _libssh2_channel_read(channel, stream_id, buf, buflen));
     return rc;
diff --git a/src/sftp.c b/src/sftp.c
index 4f846c59..45e04399 100644
--- a/src/sftp.c
+++ b/src/sftp.c
@@ -1111,8 +1111,10 @@ static ssize_t sftp_read(LIBSSH2_SFTP_HANDLE * handle, char *buffer,
        having been acked - until we reach EOF. */
     if(!filep->eof) {
         size_t max_read_ahead = buffer_size*4;
-        if(max_read_ahead > LIBSSH2_CHANNEL_WINDOW_DEFAULT*30)
-            max_read_ahead = LIBSSH2_CHANNEL_WINDOW_DEFAULT*30;
+        unsigned long recv_window;
+
+        if(max_read_ahead > LIBSSH2_CHANNEL_WINDOW_DEFAULT*4)
+            max_read_ahead = LIBSSH2_CHANNEL_WINDOW_DEFAULT*4;
 
         /* if the buffer_size passed in now is smaller than what has already
            been sent, we risk getting count become a very large number */
@@ -1137,6 +1139,26 @@ static ssize_t sftp_read(LIBSSH2_SFTP_HANDLE * handle, char *buffer,
            buffer_size*4 amount of data so that we can return them very fast
            in subsequent calls.
         */
+
+        recv_window = libssh2_channel_window_read_ex(sftp->channel,
+                                                     NULL, NULL);
+        if(max_read_ahead > recv_window) {
+            /* more data will be asked for than what the window currently
+               allows, expand it! */
+
+            if(total_read)
+                /* since we risk getting EAGAIN below, we return here if
+                   there is data available */
+                return total_read;
+
+            rc = _libssh2_channel_receive_window_adjust(sftp->channel,
+                                                        max_read_ahead*8,
+                                                        0, NULL);
+            /* if this returns EAGAIN, we will get back to this function
+               at next call */
+            if (rc)
+                return rc;
+        }
     }
 
     while(count > 0) {