There are posts all over the net from linux users with RTL8111/8168B experiencing poor network performance (usually lots of dropped packets). The best solution seems to be to blacklist the r8169 driver and use the r8168 driver instead.
E.g. see: http://forums.linuxmint.com/viewtopic.php?f=49&t=80757 or http://www.foxhop.net/realtek-dropping-packets-on-linux-ubuntu-and- fedora And lots of Ubuntu bugs: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/347711 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/864196 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/839393 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/853671 I experienced the problem with a new motherboard using onboard LAN. Symptoms were very poor network performance, lots of dropped packets revealed by 'ifconfig', 'dmesg' reporting lots of 'link up', 'link down' messages, and occasionally errors like: [ 412.621426] ------------[ cut here ]------------ [ 412.621437] WARNING: at /build/buildd/linux-3.0.0/net/sched/sch_generic.c:255 dev_watchdog+0x25a/0x270() [ 412.621440] Hardware name: Z68AP-D3 [ 412.621442] NETDEV WATCHDOG: eth5 (r8169): transmit queue 0 timed out [ 412.621444] Modules linked in: pci_stub vboxpci vboxnetadp vboxnetflt vboxdrv nvidia(P) snd_hda_codec_hdmi snd_hda_codec_realte k snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi snd_rawmidi i915 joydev snd_seq_midi_event snd_seq snd_timer snd_seq_ device snd dm_multipath drm_kms_helper binfmt_misc drm soundcore i2c_algo_bit ppdev video snd_page_alloc mei(C) parport_pc serio_r aw hwmon_vid coretemp firewire_sbp2 firewire_core crc_itu_t lp parport raid10 raid456 async_pq async_xor xor async_memcpy async_ra id6_recov hid_microsoft usbhid hid r8169 raid6_pq async_tx xhci_hcd raid1 raid0 multipath linear [last unloaded: vmnet] [ 412.621495] Pid: 0, comm: swapper Tainted: P C 3.0.0-14-generic #23-Ubuntu [ 412.621498] Call Trace: [ 412.621500] <IRQ> [<ffffffff8105e7ef>] warn_slowpath_common+0x7f/0xc0 [ 412.621509] [<ffffffff8105e8e6>] warn_slowpath_fmt+0x46/0x50 [ 412.621515] [<ffffffff814f832a>] dev_watchdog+0x25a/0x270 [ 412.621520] [<ffffffff81011663>] ? native_sched_clock+0x13/0x60 [ 412.621524] [<ffffffff810116b9>] ? sched_clock+0x9/0x10 [ 412.621528] [<ffffffff814f80d0>] ? qdisc_reset+0x50/0x50 [ 412.621531] [<ffffffff814f80d0>] ? qdisc_reset+0x50/0x50 [ 412.621536] [<ffffffff8106d546>] call_timer_fn+0x46/0x160 [ 412.621542] [<ffffffff812ef45d>] ? rb_insert_color+0xad/0x150 [ 412.621545] [<ffffffff814f80d0>] ? qdisc_reset+0x50/0x50 [ 412.621549] [<ffffffff8106ee72>] run_timer_softirq+0x132/0x2a0 [ 412.621554] [<ffffffff8102706d>] ? lapic_next_event+0x1d/0x30 [ 412.621558] [<ffffffff81065f08>] __do_softirq+0xa8/0x210 [ 412.621563] [<ffffffff8109382f>] ? tick_program_event+0x1f/0x30 [ 412.621567] [<ffffffff815f48dc>] call_softirq+0x1c/0x30 [ 412.621571] [<ffffffff8100c2d5>] do_softirq+0x65/0xa0 [ 412.621574] [<ffffffff810662ee>] irq_exit+0x8e/0xb0 [ 412.621578] [<ffffffff815f521e>] smp_apic_timer_interrupt+0x6e/0x99 [ 412.621581] [<ffffffff815f4093>] apic_timer_interrupt+0x13/0x20 [ 412.621584] <EOI> [<ffffffff8134a73b>] ? intel_idle+0xcb/0x120 [ 412.621593] [<ffffffff8134a71d>] ? intel_idle+0xad/0x120 [ 412.621597] [<ffffffff814ac68d>] cpuidle_idle_call+0x9d/0x280 [ 412.621603] [<ffffffff8100920b>] cpu_idle+0xab/0x100 [ 412.621609] [<ffffffff815b958e>] rest_init+0x72/0x74 [ 412.621613] [<ffffffff81ad0c2b>] start_kernel+0x3d4/0x3df [ 412.621617] [<ffffffff81ad0388>] x86_64_start_reservations+0x132/0x136 [ 412.621620] [<ffffffff81ad0140>] ? early_idt_handlers+0x140/0x140 [ 412.621624] [<ffffffff81ad0459>] x86_64_start_kernel+0xcd/0xdc [ 412.621626] ---[ end trace 215a139142e0369d ]--- [ 412.637541] r8169 0000:04:00.0: eth5: link up I have no problems since manually installing the r8168 driver instead. $ sudo lshw -class network *-network description: Ethernet interface product: RTL8111/8168B PCI Express Gigabit Ethernet controller vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:04:00.0 logical name: eth5 version: 06 serial: 50:e5:49:4d:36:84 size: 1Gbit/s capacity: 1Gbit/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=r8168 driverversion=8.023.00-NAPI duplex=full ip=192.168.0.2 latency=0 link=yes multicast=yes port=twisted pair speed=1Gbit/s resources: irq:42 ioport:ee00(size=256) memory:fbdff000-fbdfffff memory:fbdf8000-fbdfbfff $ sudo lspci -v ... 04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06) Subsystem: Giga-byte Technology GA-EP45-DS5 Motherboard Flags: bus master, fast devsel, latency 0, IRQ 42 I/O ports at ee00 [size=256] Memory at fbdff000 (64-bit, prefetchable) [size=4K] Memory at fbdf8000 (64-bit, prefetchable) [size=16K] Capabilities: [40] Power Management version 3 Capabilities: [50] MSI: Enable+ Count=1/1 Maskable- 64bit+ Capabilities: [70] Express Endpoint, MSI 01 Capabilities: [b0] MSI-X: Enable- Count=4 Masked- Capabilities: [d0] Vital Product Data Capabilities: [100] Advanced Error Reporting Capabilities: [140] Virtual Channel Capabilities: [160] Device Serial Number 01-00-00-00-68-4c-e0-00 Kernel driver in use: r8168 Kernel modules: r8168 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/699761 Title: Realtek RTL8111/8168B REV 6 PCI-E NIC bad performance To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/699761/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
