# IntelÃ‚Â® 82574L 100Kbs SLOW



## rpoyner (Jan 17, 2013)

*IntelÂ® 82574L 100Kbs SLOW*

I'm new to FreeBSD, but not to Unix.

I have a server with a SuperMicro X8ST3-F mother board and an onboard intel 82574L dual-port gigabit controller. The system is running FreeBSD 9.1.

With iperf I measure anywhere from 100 to 400 Kbs throughput with the FreeBSD machine running as the iperf server and a remote machine as the client. When the FreeBSD machine is the client and the remote the server I get 2 or 3 times that. The remote machine is a Windows 7 box connected to the same switch as the FreeBSD box. iperf gives full (100M) speed to/from the Windows box from other machines on the network.

netstat -wI 5 shows packet errors at about 10% of the total inbound packets, but no errors on outbound packets.

Things I've tried, 

Different cable and switch.

Disabling txcsum and friends with ifconfig(8).

None of which seemed to matter.

Is the Intel 82574L supported in FreeBSD 9.1?

Thanks
Russ Poyner


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## Anonymous (Jan 17, 2013)

Try whether sysctl net.inet.tcp.delayed_ack=0 makes a difference.


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## wblock@ (Jan 17, 2013)

The 82574L is supported by the em(4) driver.  I'm using one right now, but it's just a single-port card.

The best place to ask would be the freebsd-net mailing list.


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## rpoyner (Jan 17, 2013)

It's getting weird.

The terrible performance was observed when the FreeBSD machine was connected to a Cisco switch. When I put an old 100M HP switch between the FreeBSD box and the Cisco iperf gives 95Mbs all around. I don't control the Cisco switch, but I wonder if folks have seen this type of failed negotiation between FreeBSD and Cisco before. It would be helpful to have some ideas when I go pester the NOC folks.

Thanks
RP


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## rpoyner (Jan 17, 2013)

*Solved -- It was a hardware problem*

Thanks to those of you who responded. 

This turned out to be a case of a bad network port on the motherboard. The other port runs at gigabit speed without error.

Russ Poyner


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