| Message ID | 20210311203506.3450792-1-eric.dumazet@gmail.com |
|---|---|
| Headers | show |
| Series | tcp: better deal with delayed TX completions | expand |
On Thu, 11 Mar 2021 12:35:03 -0800 Eric Dumazet wrote: > From: Eric Dumazet <edumazet@google.com> > > Jakub and Neil reported an increase of RTO timers whenever > TX completions are delayed a bit more (by increasing > NIC TX coalescing parameters) > > While problems have been there forever, second patch might > introduce some regressions so I prefer not backport > them to stable releases before things settle. > > Many thanks to FB team for their help and tests. > > Few packetdrill tests need to be changed to reflect > the improvements brought by this series. FWIW I run some workloads with this for a day and looks good: Tested-by: Jakub Kicinski <kuba@kernel.org> Thank you!
On Fri, Mar 12, 2021 at 2:05 PM Yuchung Cheng <ycheng@google.com> wrote: > > On Fri, Mar 12, 2021 at 10:18 AM Jakub Kicinski <kuba@kernel.org> wrote: > > > > On Thu, 11 Mar 2021 12:35:03 -0800 Eric Dumazet wrote: > > > From: Eric Dumazet <edumazet@google.com> > > > > > > Jakub and Neil reported an increase of RTO timers whenever > > > TX completions are delayed a bit more (by increasing > > > NIC TX coalescing parameters) > > > > > > While problems have been there forever, second patch might > > > introduce some regressions so I prefer not backport > > > them to stable releases before things settle. > > > > > > Many thanks to FB team for their help and tests. > > > > > > Few packetdrill tests need to be changed to reflect > > > the improvements brought by this series. > > > > FWIW I run some workloads with this for a day and looks good: > > > > Tested-by: Jakub Kicinski <kuba@kernel.org> > Acked-by: Yuchung Cheng <ycheng@google.com> > Thank you Eric for fixing the bug. The series looks good to me as well. Re this one: - WARN_ON(tp->retrans_out != 0); + WARN_ON(tp->retrans_out != 0 && !tp->syn_data); it seems a little unfortunate to lose the power of this WARN_ON for the lifetime of TFO connections, but I do not have a better idea. :-) thanks, neal
From: Eric Dumazet <edumazet@google.com> Jakub and Neil reported an increase of RTO timers whenever TX completions are delayed a bit more (by increasing NIC TX coalescing parameters) While problems have been there forever, second patch might introduce some regressions so I prefer not backport them to stable releases before things settle. Many thanks to FB team for their help and tests. Few packetdrill tests need to be changed to reflect the improvements brought by this series. Eric Dumazet (3): tcp: plug skb_still_in_host_queue() to TSQ tcp: consider using standard rtx logic in tcp_rcv_fastopen_synack() tcp: remove obsolete check in __tcp_retransmit_skb() include/linux/skbuff.h | 2 +- net/ipv4/tcp_input.c | 10 ++++------ net/ipv4/tcp_output.c | 20 ++++++++------------ 3 files changed, 13 insertions(+), 19 deletions(-)