Network is unstable with Intel 82540EM ethernet card

[Nicolas Dumoulin]

Since I've upgraded my workstation to feisty, the network is very unstable. I've also tried to make a fresh install with the beta and the bug is the same.

Network downloading frequently stop (very hard to make an upgrade) with several soft (includes wget).
Web pages viewing needs to repeat request (by page reloading) several times to obtain a page.

My workstation is a Dell Precision 360, and the ethernet card is a "Intel Corporation 82540EM Gigabit Ethernet Controller (rev 02)".

I think that the problem could be in the kernel module for my ethernet card, but I don't know how to confirm this.

[Brian Murray (brian-murray)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. Unfortunately we can't fix it, because your description doesn't yet have enough information.
Please include the following additional information, if you have not already done so (please pay attention to lspci's additional options), as required by the Ubuntu Kernel Team:
1. Please include the output of the command 'uname -a' in your next response. It should be one, long line of text which includes the exact kernel version you're running, as well as the CPU architecture.
2. Please run the command 'dmesg > dmesg.log' and attach the resulting file 'dmesg.log' to this bug report.
3. Please run the command 'sudo lspci -vvnn > lspci-vvnn.log' and attach the resulting file 'lspci-vvnn.log' to this bug report.
For your reference, the full description of procedures for kernel-related bug reports is available at https://wiki.ubuntu.com/KernelTeamBugPolicies . Thanks in advance!

[Nicolas Dumoulin (nicolas-dumoulin)]

Thanks for your answer.

Here are more details

$uname -a
Linux cfp6018 2.6.20-15-generic #2 SMP Sun Apr 15 07:36:31 UTC 2007 i686 GNU/Linux

Ethernet info in lspci output (see attached for complete output)
02:0c.0 Ethernet controller [0200]: Intel Corporation 82540EM Gigabit Ethernet Controller [8086:100e] (rev 02)
        Subsystem: Dell Unknown device [1028:0156]
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV+ VGASnoop- ParErr- Stepping- SERR+ FastB2B-
        Status: Cap+ 66MHz+ UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
        Latency: 64 (63750ns min), Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 18
        Region 0: Memory at fcee0000 (32-bit, non-prefetchable) [size=128K]
        Region 2: I/O ports at dcc0 [size=64]
        Capabilities: [dc] Power Management version 2
                Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
                Status: D0 PME-Enable- DSel=0 DScale=1 PME-
        Capabilities: [e4] PCI-X non-bridge device
                Command: DPERE- ERO+ RBC=512 OST=1
                Status: Dev=00:00.0 64bit- 133MHz- SCD- USC- DC=simple DMMRBC=2048 DMOST=1 DMCRS=16 RSCEM- 266MHz- 533MHz-
        Capabilities: [f0] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable-
                Address: 0000000000000000 Data: 0000

[Nicolas Dumoulin (nicolas-dumoulin)]

And the output of dmesg

[Nicolas Dumoulin (nicolas-dumoulin)]

A colleague has the same bug. Here are his configuration :

uname -a :
Linux CFP4075 2.6.20-15-generic #2 SMP Sun Apr 15 07:36:31 UTC 2007 i686
GNU/Linux

Ethernet info in lspci output (see attached for complete output) :
09:00.0 Ethernet controller [0200]: Broadcom Corporation NetXtreme BCM5752 Gigabit Ethernet PCI Express [14e4:1600] (rev 02)
        Subsystem: Dell Unknown device [1028:01c2]
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 18
        Region 0: Memory at dcef0000 (64-bit, non-prefetchable) [size=64K]
        Capabilities: [48] Power Management version 2
                Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot+,D3cold+)
                Status: D0 PME-Enable- DSel=0 DScale=1 PME-
        Capabilities: [50] Vital Product Data
        Capabilities: [58] Message Signalled Interrupts: Mask- 64bit+ Queue=0/3 Enable-
                Address: 7dfc7357bdedb5b0 Data: f9b0
        Capabilities: [d0] Express Endpoint IRQ 0
                Device: Supported: MaxPayload 512 bytes, PhantFunc 0, ExtTag+
                Device: Latency L0s <4us, L1 unlimited
                Device: AtnBtn- AtnInd- PwrInd-
                Device: Errors: Correctable- Non-Fatal- Fatal- Unsupported-
                Device: RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
                Device: MaxPayload 128 bytes, MaxReadReq 4096 bytes
                Link: Supported Speed 2.5Gb/s, Width x1, ASPM L0s L1, Port 0
                Link: Latency L0s <2us, L1 <64us
                Link: ASPM L1 Enabled RCB 64 bytes CommClk+ ExtSynch-
                Link: Speed 2.5Gb/s, Width x1

[Nicolas Dumoulin (nicolas-dumoulin)]

And his dmesg output (attached)

[Nicolas Dumoulin (nicolas-dumoulin)]

Well, my colleague may have found the problem.
It seems that it is a kernel configuration since 2.6.17 that is in cause.
On my machine, and those of my colleague, setting net.ipv4.tcp_rmem works fine. I've not yet tested on other machines that had similar problem ...

To set this configuration, run :
sudo sysctl -w net.ipv4.tcp_window_scaling=0
Or append "net.ipv4.tcp_window_scaling=0" in /etc/sysctl.conf

It seems (on french forums) that this configuration coulod affect local wide transfers, in this case, configuration of kernel < 2.6.17 is "net.ipv4.tcp_rmem=4096 87380 174760".

French source :
http://doc.ubuntu-fr.org/feisty_internet_problemes
http://forum.ubuntu-fr.org/viewtopic.php?pid=831529#p831529

[Launchpad Janitor (janitor)]

Beginning with the Hardy Heron 8.04 development cycle, all open Ubuntu kernel bugs need to be reported against the "linux" kernel package. We are automatically migrating this bug to the new "linux" package. However, development has already began for the upcoming Intrepid Ibex 8.10 release. It would be helpful if you could test the upcoming release and verify if this is still an issue - http://www.ubuntu.com/testing . If the issue still exists, please update this report by changing the Status of the "linux" task from "Incomplete" to "New". We appreciate your patience and understanding as we make this transition. Thanks!

[Leann Ogasawara (leannogasawara)]

The Ubuntu Kernel Team is planning to move to the 2.6.27 kernel for the upcoming Intrepid Ibex 8.10 release. As a result, the kernel team would appreciate it if you could please test this newer 2.6.27 Ubuntu kernel. There are one of two ways you should be able to test:

1) If you are comfortable installing packages on your own, the linux-image-2.6.27-* package is currently available for you to install and test.

--or--

2) The upcoming Alpha5 for Intrepid Ibex 8.10 will contain this newer 2.6.27 Ubuntu kernel. Alpha5 is set to be released Thursday Sept 4. Please watch http://www.ubuntu.com/testing for Alpha5 to be announced. You should then be able to test via a LiveCD.

Please let us know immediately if this newer 2.6.27 kernel resolves the bug reported here or if the issue remains. More importantly, please open a new bug report for each new bug/regression introduced by the 2.6.27 kernel and tag the bug report with 'linux-2.6.27'. Also, please specifically note if the issue does or does not appear in the 2.6.26 kernel. Thanks again, we really appreicate your help and feedback.

[Launchpad Janitor (janitor)]

Per a decision made by the Ubuntu Kernel Team, bugs will longer be assigned to the ubuntu-kernel-team in Launchpad as part of the bug triage process. The ubuntu-kernel-team is being unassigned from this bug report. Refer to https://wiki.ubuntu.com/KernelTeamBugPolicies for more information. Thanks.

[Nicolas Dumoulin (nicolas-dumoulin)]

This bug is fixed with Intrepid version and new kernel.
Thanks.