On Fri, 2015-02-06 at 05:40 -0800, Eric Dumazet wrote: > tcp_wfree() could maintain in tp->tx_completion_delay_ms an EWMA > of TX completion delay. But this would require yet another expensive > call to ktime_get() if HZ < 1000. > > Then tcp_write_xmit() could use it to adjust : > > limit = max(2 * skb->truesize, sk->sk_pacing_rate >> 9); > > to > > amount = (2 + tp->tx_completion_delay_ms) * sk->sk_pacing_rate > > limit = max(2 * skb->truesize, amount / 1000); > > I'll cook a patch.
Hmm... doing this in all protocols would be too expensive, and we do not want to include time spent in qdiscs. wifi could eventually do that, providing in skb->tx_completion_delay_us the time spent in wifi driver. This way, we would have no penalty for network devices doing normal skb orphaning (loopback interface, ethernet, ...) -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
