@MfA: There shouldn't be any limit on data send speed, selects unblock, as soon as the driver has room for more data. Both client and server prefetch frames. As soon as the client has decompressed the received frame, it requests the next frame, before delivering the frame to the next filter. If the server is idle more than 1msec after delivering a frame, it will automatically start preparing the next. The 2.6 version is slightly more sophiticated than the 2.5, which I have stopped adding features to a while ago.