packet drop since upgrade from 4.0 to 4.0.2

[ka2er]

Hi,

I've got an intel nuc with a

03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 0c)

Since the upgrade from 4.0 to 4.0.2 I get many drop packets

eth0      Link encap:Ethernet  HWaddr C0:3F:D5:63:0A:C3  
          inet addr:192.168.0.15  Bcast:192.168.0.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:7200  Metric:1
          RX packets:219323 errors:0 dropped:67 overruns:0 frame:0
          TX packets:134287 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1348006771 (1.2 GiB)  TX bytes:13022915 (12.4 MiB)

=> 67

modules loaded

odule                  Size  Used by
ir_lirc_codec           3765  0 
lirc_dev                7787  1 ir_lirc_codec
ir_mce_kbd_decoder      2831  0 
snd_hda_codec_hdmi     30179  1 
ir_sanyo_decoder        1437  0 
ir_jvc_decoder          1497  0 
ir_sony_decoder         1435  0 
ir_rc6_decoder          1914  0 
snd_hda_codec_realtek    40820  1 
snd_hda_codec_generic    39966  1 snd_hda_codec_realtek
ir_rc5_decoder          1433  0 
ir_nec_decoder          1497  0 
iwlmvm                 97599  0 
mac80211              220442  1 iwlmvm
rc_rc6_mce              1268  0 
btusb                  14219  0 
bluetooth             188397  2 btusb
6lowpan_iphc            4053  1 bluetooth
snd_hda_intel          29715  2 
intel_rapl              7883  0 
iwlwifi                70288  1 iwlmvm
snd_hda_codec          70871  4 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_codec_generic,snd_hda_intel
snd_hwdep               4757  1 snd_hda_codec
snd_pcm                59081  4 snd_hda_codec_hdmi,snd_hda_codec,snd_hda_intel
cfg80211              175500  3 iwlwifi,mac80211,iwlmvm
ite_cir                12943  0 
rc_core                11038  12 lirc_dev,ir_lirc_codec,ir_rc5_decoder,ir_nec_decoder,ir_sony_decoder,ir_mce_kbd_decoder,ir_jvc_decoder,ir_rc6_decoder,ir_sanyo_decoder,ite_cir,rc_rc6_mce
xhci_hcd               80853  0 

kernel

Linux xbmc 3.14.4 #1 SMP Mon May 19 10:03:40 CEST 2014 x86_64 GNU/Linux

dmesg concerning net driver

[    1.173768] r8169 Gigabit Ethernet driver 2.3LK-NAPI loaded
[    1.173785] r8169 0000:03:00.0: can't disable ASPM; OS doesn't have ASPM control
[    1.179653] r8169 0000:03:00.0: irq 105 for MSI/MSI-X
[    1.179855] r8169 0000:03:00.0 eth0: RTL8168g/8111g at 0xffffc90000648000, c0:3f:d5:63:0a:c3, XID 0c000800 IRQ 105
[    1.179860] r8169 0000:03:00.0 eth0: jumbo features [frames: 9200 bytes, tx checksumming: ko]

Do you need more debug infos ?

[fritsch]

Could you copy 50gb to /dev/null and gather some more stats?

[stefansaraev]

really? I hope that's not a joke. 67 of 219323... fix the damn network infrastructure to have 0.00000001% loss.

[stefansaraev]

dude, that's r8169, 67 of 219323 is PERFECT. you can't get mor (err: better)

[stefansaraev]

FYI drops can be caused by lot of things.

• bad cable / switch
• ring buffer overfflow (driver.. try increasing, hint: ethtool)
• (ab)normal rx rate (100+mbps with r8169 will easily trigger it, go phone call realtek.com.tw to ask why), experimenting with iperf, enabling "wifi tethering" (conntrack)

[ka2er]

sorry for my late response but my report was bad as you already said. The problem was a bad cable (thanks for the input). This little amount of drop packets was making impossible to watch movie, the player was re-buffering every 2 mins.