Arch Linux

whipsch

Member

Registered: 2009-06-04

Posts: 4

[SOLVED] Network speed very slow, no apparent reason

Hello, recently I switched from Windows 7 RC1 to Arch on my home machine (I have used Gentoo, Ubuntu, and Fedora 10 on the same machine in the past), and for some reason network speed is very slow.

I have Verizon's 20mbit/5mbit package, and I have always gotten that speed.
Using speedtest.net and 100mb.test from cachefly on multiple computers I have come to the conclusion that it is infact my Arch install that is causing the problem:
- All other machines on my network are getting 20/5 (both wired and wireless)
- I ran a speedtest from 2 other machines using the ethernet cable that this PC is on.  Again, full 20/5.
- scp transfer of 100mb.test from this PC -> other Arch box: ~2.8MB/s.
- scp transfer of 100mb.test from other Arch box -> this PC: ~2.8MB/s.
- scp transfer of 100mb.test from this PC -> UK VPS (100mbit line): ~539KB/s
- scp transfer of 100mb.test from UK VPS -> this PC: ~76KB/s
- scp transfer of 100mb.test from this PC -> Chicago Server (dual gbit lines): ~563KB/s
- scp transfer of 100mb.test from Chicago Server -> this PC: ~91KB/s

speedtest.net result:

Upload speed seems to be unaffected.

I have tried disabling TCP window scaling, and appending my hostname to /etc/hosts.
What is weird though is that the other Arch box has an identical network config,  I don't see any reason why it shouldn't work.

My NIC is an integrated Realtek something, I can get the exact model if needed.

Last edited by whipsch (2009-06-05 18:29:21)

JF

Member

From: France

Registered: 2009-03-27

Posts: 39

Re: [SOLVED] Network speed very slow, no apparent reason

Hi, whipsch

Can you try ethtool to see if your ethernet card is actually negociating and using a 100Mb full duplex link on your LAN ? If not you can try to force the link parameter with ethtool. Also maybe the driver of your NIc has options related to link negociation.

Hope this helps,

JF

whipsch

Member

Registered: 2009-06-04

Posts: 4

Re: [SOLVED] Network speed very slow, no apparent reason

Hi.

ethtool reports that link speed is 1Gbit full duplex (I don't know why it defaulted to 1Gbit, but that's not important right now).

Last edited by whipsch (2009-06-05 00:33:29)

decaren

Member

Registered: 2009-04-17

Posts: 24

Re: [SOLVED] Network speed very slow, no apparent reason

Do your host names match in rc.conf and hosts?  Been there and it's about the same as what you are experiencing

whipsch

Member

Registered: 2009-06-04

Posts: 4

Re: [SOLVED] Network speed very slow, no apparent reason

Yes they do match

Problem solved.  Turns out the first port on my NIC was bad, switched to second port and all is well.

Thanks.

Last edited by whipsch (2009-06-05 18:29:11)