[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <alpine.WNT.2.00.1004271110300.4368@jbrandeb-desk1.amr.corp.intel.com>
Date: Tue, 27 Apr 2010 11:32:39 -0700 (Pacific Daylight Time)
From: "Brandeburg, Jesse" <jesse.brandeburg@...el.com>
To: "R. Weinedel" <r.weinedel@...oo.de>
cc: "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: vlan performance issue on outgoing traffic
On Sun, 25 Apr 2010, R. Weinedel wrote:
> hallo,
>
> I have an performance issue with vlan interfaces on an Debian Lenny
> server. The problem occurs only on outgoing traffic from the vlan
> interfaces. They use only half of the available bandwidth - (490 Mbit/s
> measured with iperf ). Incoming traffic is handled @ 950 Mbit/s and is
> fine. The issue remains even with no switch and an direct connection
> between pc and server on the same nic. Removing (on server) the vlans
> from eth0 and configure one net on eth0 results in full speed (950
> Mbit/s) in both directions. Even another nic (onboard nvidia3 - mod
> forcedeth) couldn't solve it. I tested only in the same networking
> segment (vlan) without the need for ip forwarding or NAT, but the issue
> occurs on all my vlan's.
>
> All values were taken with iperf between the server and an ubuntu 9.04
> workstation (and vice versa). I have controlled (w. ethtool / stats from
> switch) that all connection was 1000-BaseT/full duplex. It looks like
> some kind of trafficshaping to me, but i don't use tc, qos,tos nor other
> priority handling.
> The network ist quite simple: One Server, one switch and then the
> workstations. No need for cascading or using (r)stp.
>
> Here some information about my network:
>
> Switch: Netgear GSM7224 Layer 2 managed switch, FW 6.2.0.14
> (independent, issue remains on direct connection).
>
> Server: Debian Lenny, kernel 2.6.26-2,
This version of the kernel doesn't support offloads for vlan adapters,
which is probably causing most of your decrease in throughput due to
either exhausting socket buffer size, or because of the round trip time
being so much more relevant when not sending large bursts using TSO.
Sometimes the flood of ACK packets causes higher cpu which could reduce
your throughput also.
The newer kernels will have a major impact on your setup due to a patch
that enabled pass through of hardware offloads to the vlan device's
offload advertisement.
The commit id of the patch is 5fb13570543f4ae022996c9d7c0c099c8abf22dd,
you can view it at:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=5fb13570543f4ae022996c9d7c0c099c8abf22dd
> NIC: Intel Corporation 82541PI Gigabit Ethernet Con. (e1000 module).
This PCI adapter is bandwidth limited on the PCI bus, and so will be even
more sensitive to offload on (TSO) vs offload off.
> # ethtool eth0
> Settings for eth0:
> Supported ports: [ TP ]
> Supported link modes: 10baseT/Half 10baseT/Full
> 100baseT/Half 100baseT/Full
> 1000baseT/Full
> Supports auto-negotiation: Yes
> Advertised link modes: 1000baseT/Full
> Advertised auto-negotiation: Yes
> Speed: 1000Mb/s
> Duplex: Full
> Port: Twisted Pair
> PHYAD: 0
> Transceiver: internal
> Auto-negotiation: on
> Supports Wake-on: umbg
> Wake-on: g
> Current message level: 0x00000007 (7)
> Link detected: yes
>
> 8021q:
> filename: /lib/modules/2.6.26-2-686/kernel/net/8021q/8021q.ko
> version: 1.8
> license: GPL
> alias: rtnl-link-vlan
> srcversion: A61E1168F65EE335A91D4E1
> depends:
> vermagic: 2.6.26-2-686 SMP mod_unload modversions 686
>
> VLAN: #/proc/net/vlan/config
> VLAN Dev name | VLAN ID
> Name-Type: VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD
> eth0.5 | 5 | eth0
> eth0.101 | 101 | eth0
> eth0.90 | 90 | eth0
>
> IFCONFIG:
> eth0 Link encap:Ethernet Hardware Adresse 00:0e:0c:bc:43:43
> inet6-Adresse: fe80::20e:cff:febc:4343/64
> Gültigkeitsbereich:Verbindung
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metrik:1
> RX packets:28140829 errors:0 dropped:218 overruns:0 frame:0
> TX packets:44994420 errors:0 dropped:0 overruns:0 carrier:0
> Kollisionen:0 Sendewarteschlangenlänge:1000
> RX bytes:3472864138 (3.2 GiB) TX bytes:3908682627 (3.6 GiB)
>
> eth0.5 Link encap:Ethernet Hardware Adresse 00:0e:0c:bc:43:43
> inet Adresse:XXX.YYY.5.1 Bcast:XXX.YYY.5.255 Maske:255.255.255.0
> inet6-Adresse: fe80::20e:cff:febc:4343/64
> Gültigkeitsbereich:Verbindung
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metrik:1
> RX packets:77807 errors:0 dropped:0 overruns:0 frame:0
> TX packets:69699 errors:0 dropped:0 overruns:0 carrier:0
> Kollisionen:0 Sendewarteschlangenlänge:0
> RX bytes:57578233 (54.9 MiB) TX bytes:7782844 (7.4 MiB)
>
> eth0.90 Link encap:Ethernet Hardware Adresse 00:0e:0c:bc:43:43
> inet Adresse:XXX.YYY.90.1 Bcast:XXX.YYY.90.255
> Maske:255.255.255.0
> inet6-Adresse: fe80::20e:cff:febc:4343/64
> Gültigkeitsbereich:Verbindung
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metrik:1
> RX packets:457850 errors:0 dropped:0 overruns:0 frame:0
> TX packets:913988 errors:0 dropped:0 overruns:0 carrier:0
> Kollisionen:0 Sendewarteschlangenlänge:0
> RX bytes:23824841 (22.7 MiB) TX bytes:1311485281 (1.2 GiB)
>
> eth0.101 Link encap:Ethernet Hardware Adresse 00:0e:0c:bc:43:43
> inet Adresse:XXX.YYY.101.1 Bcast:XXX.YYY.101.255
> Maske:255.255.255.0
> inet6-Adresse: fe80::20e:cff:febc:4343/64
> Gültigkeitsbereich:Verbindung
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metrik:1
> RX packets:24856818 errors:0 dropped:0 overruns:0 frame:0
> TX packets:41608593 errors:0 dropped:0 overruns:0 carrier:0
> Kollisionen:0 Sendewarteschlangenlänge:0
> RX bytes:423116676 (403.5 MiB) TX bytes:3855703636 (3.5 GiB)
>
> ROUTE: #route -n
> Ziel Router Genmask Flags Metric Ref Use
> Iface
> XXX.YYY.101.0 0.0.0.0 255.255.255.0 U 0 0 0
> eth0.101
> XXX.YYY.5.0 0.0.0.0 255.255.255.0 U 0 0 0
> eth0.5
> XXX.YYY.90.0 0.0.0.0 255.255.255.0 U 0 0 0
> eth0.90
> 0.0.0.0 192.168.5.4 0.0.0.0 UG 0 0 0
> eth0.5
>
> Can someone give me a hint, where my search for an solution should be
> going on ?
>
> Many thanks !
> Regards
> Ralf Weinedel
> Falkensee/Germany
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists