Re: r8169 Driver - Poor Network Performance Since Kernel 4.19

[David Chang <dchang@suse.com>]

Hi Heiner,

On Feb 14, 2019 at 07:17:44 +0100, Heiner Kallweit wrote:
> Hi David,
> 
> On 14.02.2019 03:45, David Chang wrote:
> > Hi Heiner,
> > 
> > On Feb 05, 2019 at 19:50:30 +0100, Heiner Kallweit wrote:
> >> Hi David,
> >>
> >> meanwhile there's the following bug report matching what reported.
> >> It's even the same chip version (RTL8168h).
> >> https://bugzilla.redhat.com/show_bug.cgi?id=1671958
> >>
> >> Symptom there is also a significant number of rx_missed packets.
> >> Could you try what I mentioned there last:
> >> Try building a kernel with the call to rtl_hw_aspm_clkreq_enable(tp, true) at the
> >> end of rtl_hw_start_8168h_1() being disabled.
> > 
> > After disabled the aspm function that you mentioned, we finally got the
> > positive testing result. And the rx_missed error was gone. If without
> > the patch, the receive side get back to bad performance.
> > 
> Good to know, thanks. I also checked with Realtek, they confirmed that their Windows
> driver uses some heuristics to disable ASPM under high load. So it seems like there
> is some hw issue. Open so far is whether this affects certain chip versions only.
> Let's see whether they can provide more information.

Ok!

> Disabling ASPM in general would hurt notebook users because based on some past
> measurements we know ASPM can significantly save energy.

I understand, thanks!

regards,
David
> 
> > kernel: r8169: loading out-of-tree module taints kernel.
> > kernel: r8169: module verification failed: signature and/or required key missing - tainting kernel
> > kernel: libphy: r8169: probed
> > kernel: r8169 0000:01:00.0 eth0: RTL8168h/8111h, ec:8e:b5:5a:2c:f5, XID 54100880, IRQ 128
> > kernel: r8169 0000:01:00.0 eth0: jumbo features [frames: 9200 bytes, tx checksumming: ko]
> > kernel: r8169 0000:01:00.0 enp1s0: renamed from eth0
> > kernel: Generic PHY r8169-100:00: attached PHY driver [Generic PHY] (mii_bus:phy_addr=r8169-100:00, irq=IGNORE)
> > kernel: r8169 0000:01:00.0 enp1s0: Link is Up - 1Gbps/Full - flow control off
> > 
> > NIC statistics:
> >      tx_packets: 1653804
> >      rx_packets: 1555966
> >      tx_errors: 0
> >      rx_errors: 0
> >      rx_missed: 0
> >      align_errors: 0
> >      tx_single_collisions: 0
> >      tx_multi_collisions: 0
> >      unicast: 1555884
> >      broadcast: 78
> >      multicast: 4
> >      tx_aborted: 0
> >      tx_underrun: 0
> > 
> > iperf receive:
> > -----------------------------------------------------------
> > Server listening on 5201
> > -----------------------------------------------------------
> > Accepted connection from 10.x.x.x, port 55516
> > [  5] local 10.x.x.x port 5201 connected to 10.x.x.x port 58172
> > [ ID] Interval           Transfer     Bitrate
> > [  5]   0.00-1.00   sec   108 MBytes   906 Mbits/sec
> > [  5]   1.00-2.00   sec   112 MBytes   941 Mbits/sec
> > [  5]   2.00-3.00   sec   112 MBytes   940 Mbits/sec
> > [  5]   3.00-4.00   sec   112 MBytes   941 Mbits/sec
> > [  5]   4.00-5.00   sec   112 MBytes   941 Mbits/sec
> > [  5]   5.00-6.00   sec   112 MBytes   942 Mbits/sec
> > [  5]   6.00-7.00   sec   112 MBytes   939 Mbits/sec
> > [  5]   7.00-8.00   sec   112 MBytes   941 Mbits/sec
> > [  5]   8.00-9.00   sec   112 MBytes   938 Mbits/sec
> > [  5]   9.00-10.00  sec   112 MBytes   941 Mbits/sec
> > [  5]  10.00-11.00  sec   112 MBytes   941 Mbits/sec
> > [...]
> > [  5]  50.00-51.00  sec   112 MBytes   941 Mbits/sec
> > [  5]  51.00-52.00  sec   112 MBytes   941 Mbits/sec
> > [  5]  52.00-53.00  sec   112 MBytes   942 Mbits/sec
> > [  5]  53.00-54.00  sec   112 MBytes   941 Mbits/sec
> > [  5]  54.00-55.00  sec   111 MBytes   934 Mbits/sec
> > [  5]  55.00-56.00  sec   112 MBytes   942 Mbits/sec
> > [  5]  56.00-57.00  sec   112 MBytes   937 Mbits/sec
> > [  5]  57.00-58.00  sec   112 MBytes   941 Mbits/sec
> > [  5]  58.00-59.00  sec   111 MBytes   932 Mbits/sec
> > [  5]  59.00-60.00  sec   112 MBytes   942 Mbits/sec
> > [  5]  60.00-60.04  sec  4.06 MBytes   939 Mbits/sec
> > - - - - - - - - - - - - - - - - - - - - - - - - -
> > [ ID] Interval           Transfer     Bitrate
> > [  5]   0.00-60.04  sec  6.57 GBytes   940 Mbits/sec                  receiver
> > 
> > regards,
> > David
> > 
> Heiner
>