On Fri, 7 Jun 2019 at 19:26, Sergej Benilov <sergej.beni...@googlemail.com> wrote: > > Since commit 605ad7f184b60cfaacbc038aa6c55ee68dee3c89 "tcp: refine TSO > autosizing", > the TSQ limit is computed as the smaller of > sysctl_tcp_limit_output_bytes and max(2 * skb->truesize, sk->sk_pacing_rate > >> 10). > For some connections this approach sets a low limit, reducing throughput > dramatically. > > Add a call to skb_orphan() to sis900_start_xmit() > to speed up packets delivery from the kernel to the driver. > > Test: > netperf -H remote -l -2000000 -- -s 1000000 > > before patch: > > MIGRATED TCP STREAM TEST from 0.0.0.0 () port 0 AF_INET to remote () port 0 > AF_INET : demo > Recv Send Send > Socket Socket Message Elapsed > Size Size Size Time Throughput > bytes bytes bytes secs. 10^6bits/sec > > 87380 327680 327680 341.79 0.05 > > after patch: > > MIGRATED TCP STREAM TEST from 0.0.0.0 () port 0 AF_INET to remote () port 0 > AF_INET : demo > Recv Send Send > Socket Socket Message Elapsed > Size Size Size Time Throughput > bytes bytes bytes secs. 10^6bits/sec > > 87380 327680 327680 1.29 12.54 > > Signed-off-by: Sergej Benilov <sergej.beni...@googlemail.com> > --- > drivers/net/ethernet/sis/sis900.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/net/ethernet/sis/sis900.c > b/drivers/net/ethernet/sis/sis900.c > index fd812d2e..ca17b50c 100644 > --- a/drivers/net/ethernet/sis/sis900.c > +++ b/drivers/net/ethernet/sis/sis900.c > @@ -1604,6 +1604,7 @@ sis900_start_xmit(struct sk_buff *skb, struct > net_device *net_dev) > unsigned int index_cur_tx, index_dirty_tx; > unsigned int count_dirty_tx; > > + skb_orphan(skb); > spin_lock_irqsave(&sis_priv->lock, flags); > > /* Calculate the next Tx descriptor entry. */ > -- > 2.17.1 >
Thanks to Eric Dumazet for suggesting this patch
