From: Soheil Hassas Yeganeh <[email protected]> Date: Mon, 14 Sep 2020 17:52:09 -0400
> From: Soheil Hassas Yeganeh <[email protected]> > > If there was any event available on the TCP socket, tcp_poll() > will be called to retrieve all the events. In tcp_poll(), we call > sk_stream_is_writeable() which returns true as long as we are at least > one byte below notsent_lowat. This will result in quite a few > spurious EPLLOUT and frequent tiny sendmsg() calls as a result. > > Similar to sk_stream_write_space(), use __sk_stream_is_writeable > with a wake value of 1, so that we set EPOLLOUT only if half the > space is available for write. > > Signed-off-by: Soheil Hassas Yeganeh <[email protected]> > Signed-off-by: Eric Dumazet <[email protected]> Applied.
