View Full Version : [other] Random, slow internet connection

January 13th, 2013, 12:06 PM
Hello guys,
I have a strange problem with my internet connection.
At random intervals of time, speed drops from @90Mb/s to 7-8 Mb/s.
If i disable/enable my eth0 then it works again at 90Mb/s.

I'm using Linux Mint 14 on this desktop. It's a 64bit system.

PS: I'm not a very experienced user.
Thanks !

System: Host: alex-System Kernel: 3.5.0-17-generic x86_64 (64 bit, gcc: 4.7.2) Desktop: N/A Distro: Linux Mint 14 Nadia
Network: Card-1: Realtek RTL8169 PCI Gigabit Ethernet Controller driver: r8169 ver: 2.3LK-NAPI port: d100 bus-ID: 06:01.0
Card-2: Realtek RTL-8139/8139C/8139C+ driver: 8139too ver: 0.9.28 port: d000 bus-ID: 06:02.0

The problem is with the Gigabit NIC. If I use the other one it works normally.

January 13th, 2013, 02:51 PM
Please show:

cat /etc/udev/rules.d/70-persistent-net.rules
ifconfig -a

January 13th, 2013, 03:59 PM
alex-System network # cat /etc/udev/rules.d/70-persistent-net.rules

# PCI device 0x10ec:/sys/devices/pci0000:00/0000:00:1c.7/0000:04:00.0/0000:05:02.0 (8139too)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:e0:4c:7a:d8:94", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"

# PCI device 0x10ec:/sys/devices/pci0000:00/0000:00:1c.7/0000:04:00.0/0000:05:01.0 (r8169)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:14:d1:22:b8:ea", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"

# USB device 0x0bda:0x8171 (usb)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:14:d1:e5:78:c9", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="wlan*", NAME="wlan0"

I must point here that the USB device is no longer in use !(unplugged)

alex-System network # ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:14:d1:22:b8:ea
inet6 addr: fe80::214:d1ff:fe22:b8ea/64 Scope:Link
RX packets:6171 errors:0 dropped:0 overruns:0 frame:0
TX packets:719 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:781804 (781.8 KB) TX bytes:97242 (97.2 KB)

eth1 Link encap:Ethernet HWaddr 00:e0:4c:7a:d8:94
inet addr: Bcast: Mask:
inet6 addr: fe80::2e0:4cff:fe7a:d894/64 Scope:Link
RX packets:8 errors:0 dropped:0 overruns:0 frame:0
TX packets:12 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:616 (616.0 B) TX bytes:904 (904.0 B)

lo Link encap:Local Loopback
inet addr: Mask:
inet6 addr: ::1/128 Scope:Host
RX packets:18 errors:0 dropped:0 overruns:0 frame:0
TX packets:18 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1124 (1.1 KB) TX bytes:1124 (1.1 KB)

ppp0 Link encap:Point-to-Point Protocol
inet addr: P-t-P: Mask:
RX packets:685 errors:0 dropped:0 overruns:0 frame:0
TX packets:675 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:415406 (415.4 KB) TX bytes:80546 (80.5 KB)

PS: I use pppoe to connect to my isp (on interface eth0)

alex-System network # lsmod
Module Size Used by
xt_TCPMSS 12707 1
xt_tcpmss 12501 1
xt_tcpudp 12603 1
iptable_mangle 12695 1
ip_tables 26995 1 iptable_mangle
x_tables 29711 5 xt_TCPMSS,xt_tcpmss,xt_tcpudp,iptable_mangle,ip_ta bles
pppoe 17873 2
pppox 13342 1 pppoe
pci_stub 12622 1
vboxpci 23157 0
vboxnetadp 25670 0
vboxnetflt 23442 0
vboxdrv 320371 3 vboxpci,vboxnetadp,vboxnetflt
parport_pc 32688 0
ppdev 17073 0
rfcomm 46619 0
bnep 18140 0
bluetooth 209199 4 rfcomm,bnep
binfmt_misc 17500 1
snd_hda_codec_hdmi 32007 4
joydev 17457 0
coretemp 13400 0
kvm_intel 132759 0
kvm 414070 1 kvm_intel
snd_hda_codec_realtek 77876 1
ghash_clmulni_intel 13180 0
aesni_intel 51037 0
cryptd 20403 2 ghash_clmulni_intel,aesni_intel
aes_x86_64 17208 1 aesni_intel
hid_generic 12493 0
eeepc_wmi 13109 0
asus_wmi 24088 1 eeepc_wmi
sparse_keymap 13890 1 asus_wmi
gspca_sonixj 33232 0
gspca_main 28322 1 gspca_sonixj
videodev 120309 1 gspca_main
snd_hda_intel 33491 0
snd_hda_codec 134212 3 snd_hda_codec_hdmi,snd_hda_codec_realtek,snd_hda_i ntel
snd_hwdep 13602 1 snd_hda_codec
snd_pcm 96580 3 snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec
usbhid 46947 0
hid 100366 2 hid_generic,usbhid
snd_seq_midi 13324 0
snd_rawmidi 30512 1 snd_seq_midi
snd_seq_midi_event 14899 1 snd_seq_midi
snd_seq 61521 2 snd_seq_midi,snd_seq_midi_event
snd_timer 29425 2 snd_pcm,snd_seq
snd_seq_device 14497 3 snd_seq_midi,snd_rawmidi,snd_seq
psmouse 95552 0
serio_raw 13215 0
mac_hid 13205 0
snd 78734 10 snd_hda_codec_hdmi,snd_hda_codec_realtek,snd_hda_i ntel,snd_hda_codec,snd_hwdep,snd_pcm,snd_rawmidi,s nd_seq,snd_timer,snd_seq_device
microcode 22803 0
nouveau 895609 2
ttm 83595 1 nouveau
drm_kms_helper 46784 1 nouveau
drm 275528 4 nouveau,ttm,drm_kms_helper
i2c_algo_bit 13413 1 nouveau
mxm_wmi 12979 1 nouveau
video 19335 1 nouveau
wmi 19070 3 asus_wmi,nouveau,mxm_wmi
lpc_ich 17061 0
soundcore 15047 1 snd
snd_page_alloc 18484 2 snd_hda_intel,snd_pcm
mei 40690 0
lp 17759 0
parport 46345 3 parport_pc,ppdev,lp
usb_storage 48838 0
r8169 61650 0
8139too 31917 0
8139cp 27234 0

January 13th, 2013, 04:22 PM
There are two drivers loaded for this device:

echo "blacklist 8139cp" | sudo tee -a /etc/modprobe.d/blacklist.conf
sudo modprobe -rfv 8139too
sudo modprobe -rfv 8139cp
sudo modprobe -v 8139too
You are using a single modem with PPPoE?

January 13th, 2013, 04:38 PM
Yes, only on eth0 I use pppoe. The other one is for my home LAN.
I did run the code listed but now I have one question.

The interface i have problems with is eth0 which uses r8169 (am I right ?) has something to do with 8139too and 8139cp drivers ? Aren't the last 2 being used by the 100MB/s adapter (eth1) ?

Thank you for helping me !

January 13th, 2013, 05:35 PM
So please show:

lspci -nnk | grep -iA2 net
Maybe the iptables cause problems?! Did you activate a firewall?

January 14th, 2013, 11:07 AM
lspci -nnk | grep -iA2 net
06:01.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8169 PCI Gigabit Ethernet Controller [10ec:8169] (rev 10)
Subsystem: Realtek Semiconductor Co., Ltd. RTL8169/8110 Family PCI Gigabit Ethernet NIC [10ec:8169]
Kernel driver in use: r8169
Kernel modules: r8169
06:02.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ [10ec:8139] (rev 10)
Subsystem: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ [10ec:8139]
Kernel driver in use: 8139too

Nope, no firewall.
I only use iptables when I want "to nat". And then I only use masquerading over the pppoe connection.
But I think settings restore after restart because I have to use the command every time I need to nat.
BTW, in Windows 7 I have no problem with any of the NICs.
Can't tell what's the problem.
After I finish a project I will do a fresh install of Ubuntu (and see what happens) but until then I really hope I can find an answer because this really bothers me.

PS: Three days ago I had the r8169 reinstalled but no change ! I used "r8169-6.017.00" downloaded from realtek website and followed instructions in readme. Things are the same as before reinstalling.
As a "workaround" I can use the second NIC as "primary" but hey.. if something doesn't work I like to fix it.

January 14th, 2013, 10:49 PM
I suppose to be sure you could try to flush the firewall rules:

sudo iptables -F

After rebooting or restarting the firewall your firewall configuration will be restored.

January 15th, 2013, 02:41 PM
This didn't work either :(.