Slow Download Speed with FC6

cfalzone · 02-22-2007, 12:53 PM

I hook my linux box and windows box up to the same internet connection through a router / switch. My linux box seemed to be getting really horrible download speeds, so I tried one of those speed test things. The windows machine is getting 5720kbps download, the linux box is getting 73kbps. On top of that a 100MB file takes 20 mins to download on the windows box and 8 hrs to download on the linux box!!

That does not make any sense to me.

Could you guys give me some pointers on how to find out why this happening and/or how to fix it? I am running Fedora Core 6. The speed test I tried is here: ((won't let me post it yet .. this is my first post -- Search google for speed test it is the first one, called Speakeasy)).

I have already tried hooking the linux box directly up to the modem to see if it was my router/switch that was causing the issue and it is not.

Thanks,
Chris F.

Additional Info:

ifconfig output:

Code:

eth0      Link encap:Ethernet  HWaddr 00:07:E9:87:EE:C7
          inet addr:192.168.1.6  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::207:e9ff:fe87:eec7/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:24816 errors:0 dropped:0 overruns:0 frame:0
          TX packets:19458 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          RX bytes:22467844 (21.4 MiB)  TX bytes:2599552 (2.4 MiB)
          Base address:0xec40 Memory:fe1c0000-fe1e0000

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:1594 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1594 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:4744156 (4.5 MiB)  TX bytes:4744156 (4.5 MiB)

Lenard · 02-23-2007, 06:15 AM

As root, turn off the ip6 networking...........

In /etc/modprobe.conf add the line: inet6 addr: alias net-pf-10 off
In /etc/sysconfig/network add/change the line: NETWORKING_IPV6=no
Edit the /etc/sysconfig/network-scripts/ifcfg-eth0 file and add/change:
IPV6INIT=no

Also do: chkconfig --level 2345 ip6tables off

When done restart the network service: service network restart

cfalzone · 02-23-2007, 10:29 AM

Quote:

Originally Posted by Lenard

As root, turn off the ip6 networking...........

In /etc/modprobe.conf add the line: inet6 addr: alias net-pf-10 off
In /etc/sysconfig/network add/change the line: NETWORKING_IPV6=no
Edit the /etc/sysconfig/network-scripts/ifcfg-eth0 file and add/change:
IPV6INIT=no

Also do: chkconfig --level 2345 ip6tables off

When done restart the network service: service network restart

Ok I did all that. Here are the files:
/etc/modprobe.conf:

Code:

alias eth0 e1000
alias snd-card-0 snd-intel8x0
options snd-card-0 index=0
options snd-intel8x0 index=0
remove snd-intel9x0 { /usr/sbin/alsactl store 0 >/dev/null 2>&1 || : ; }; /sbin/modprobe -r --ignore-remove snd-intel8x0
alias net-pf-10 off

/etc/sysconfig/network:

Code:

NETWORKING=yes
NETWORKING_IPV6=no
HOSTNAME=localhost.localdomain

/etc/sysconfig/network-scripts/ifcfg-eth0:

Code:

# Intel Corporation 82540EM Gigabit Ethernet Controller
DEVICE=eth0
BOOTPROTO=none
HWADDR=00:07:E9:87:EE:C7
ONBOOT=yes
NETMASK=255.255.255.0
IPADDR=192.168.1.6
GATEWAY=192.168.1.1
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes

It didn't seem to help, but I am going to restart then see what happens.
Thanks for the help!!

EDIT: No Change after reboot.

cfalzone · 02-23-2007, 11:15 AM

Found the key to open the door ...

After much searching I found a few articles on tcp window scaling that raised an eyebrow ... and finally I came accross the winner ...

Code:

sysctl -w net.ipv4.tcp_window_scaling=0

Fixed the problem, and putting this ...

Code:

net.ipv4.tcp_window_scaling = 0

into my /etc/sysctl.conf, plus a reboot made it permanent.
Thanks Again.
--Chris Falzone