On Fri, 2017-07-28 at 21:59 +0200, Natale Patriciello wrote:
> Hi,
> We are working on a new TCP congestion control algorithm, aiming at satisfying
> new requirements coming from current networks. For instance, adaptation to
> bandwidth/delay changes (due to mobility, dynamic switching, handover), and
> optimal exploitation of very high link capacity and efficient transmission of
> small objects, irrespective of the underlying link characteristics.
>
> TCP Wave (TCPW) replaces the window-based transmission paradigm of the
> standard
> TCP with a burst-based transmission, the ACK-clock scheduling with a
> self-managed timer and the RTT-based congestion control loop with an Ack-based
> Capacity and Congestion Estimation (ACCE) module. In non-technical words, it
> sends data down the stack when its internal timer expires, and the timing of
> the received ACKs contribute to updating this timer regularly.
>
> We tried to add this new sender paradigm without deeply touching existing
> code.
> In fact, we added four (optional) new congestion control functions:
>
> + /* get the expiration time for the send timer (optional) */
> + unsigned long (*get_send_timer_exp_time)(struct sock *sk);
> + /* no data to transmit at the timer expiration (optional) */
> + void (*no_data_to_transmit)(struct sock *sk);
> + /* the send timer is expired (optional) */
> + void (*send_timer_expired)(struct sock *sk);
> + /* the TCP has sent some segments (optional) */
> + void (*segment_sent)(struct sock *sk, u32 sent);
>
> And a timer (tp->send_timer) which uses a send callback to push data down the
> stack. If the first of these function, get_send_timer_exp_time, is not
> implemented by the current congestion control, then the timer sending timer is
> never set, therefore falling back to the old, ACK-clocked, behavior.
trimmed CC
This patch series seems to have missed recent efforts in TCP stack,
namely TCP pacing.
commit 218af599fa635b107cfe10acf3249c4dfe5e4123 ("tcp: internal
implementation for pacing") added a timer already to get fine grained
packet xmits.
I suggest you rebase your work and try to reuse existing mechanisms.
Thanks.
