Slow Internet connection

[Haines Brown]

At some point in the last few weeks it appears I experienced a major
reduction in Internet bandwidth. I address this list because I suspect
the problem is hardware related, but if I'm wrong someone might
charitably direct me elsewhere.

I'm running Debian Sqeeze, with a Realtek 8168 or 8169 chip though a
LAN cable to a modem, which has its wireless enabled for someone else
to use.

My download speed is about 2.54 Mb/s, and upload is 0.43 Mb/sec. Is it
true that with DSL broadband one should expect figures on the order of
16 and 32 Mb/s respectively?

I just experienced several download failures with large files, and
this might indicate a RAM problem or CPU overheat. But the CPU is

temp1: +43.0°C
temp2: +37.0°C

I ran memtester on 4 Gb (I have 8 Gb installed) with one iteration
and no problem reported.

[notbob]

On 2011-11-01, Haines Brown <hai...@HistoricalMaterialism.info> wrote:
> I'm running Debian Sqeeze, with a Realtek 8168 or 8169 chip though a

> LAN cable to a modem........

Bingo! I'd ask yer ISP to provide another modem. I had a Motorola
DSL/wireless modem that went bad and had them send another. It was no
better. I had my ISP send a 2nd modem. I discovered, later, both
were refurbs. I called for a onsite tech. He brought two more modems
(zyxel), different brands/models, both refurbs. He finally had to
drive back to the shop for a NIB, top of the line zyxel replacement.
It worked! Took he and myself 2 hrs or arguing and testing, but
finally fixed it. Four bad modems!!

Prior to that, I had a similar problem, but fixed it myself. It was
not the modem, but my own bad 100ft phone line from the box and my
responsibility. I merely went to RadioShack and bought a new cable.
Problem resolved. Make sure it's not your wiring before calling in
your ISP with some serious accusations, as they charge up the
ying/yang if you don't have house phone service.

nb

[Bobbie Sellers]

Just a note: I have never bought a new DSL modem, buying
all of them so far at thrift (2nd hand) stores. The original
Alcatel went bad and I have a Netgear ADSL modem router now
from that source and from a sidewalk (private) sale picked
up a later model for use when this Netgear DG834G might fail.

Maybe it is just my inherent distrust of the prices
charged for "free" equipment of any sort. My notebook is
a refurb too I believe.

bliss

[Haines Brown]

Bobbie Sellers <bliss-...@dslextreme.com> writes:

> On 11/01/2011 09:32 AM, notbob wrote:
>> On 2011-11-01, Haines Brown<hai...@HistoricalMaterialism.info> wrote:
>>> I'm running Debian Sqeeze, with a Realtek 8168 or 8169 chip though a
>>> LAN cable to a modem........
>>
>> Bingo! I'd ask yer ISP to provide another modem.

I've been using a couple D-Link 2640B modems in recent years because
they combine the wireless. Never had a problem.

Are you implying that a faulty modem is a likely cause of cause of
reduced bandwidth? If so, I'll test by trying another modem. Is there
any way to test modem bandwidth?

Haines Brown

[Trevor Hemsley]

On Tue, 1 Nov 2011 18:15:45 UTC in comp.os.linux.hardware, Haines Brown
<hai...@HistoricalMaterialism.info> wrote:

> Are you implying that a faulty modem is a likely cause of cause of
> reduced bandwidth? If so, I'll test by trying another modem. Is there
> any way to test modem bandwidth?

You said you had another machine - boot that and see what its throughput is
like. If it's good then it's not your cable modem. Try changing the cable from
your machine to the router next, that's also cheap to try out. Also look at
which driver is loading for your ethernet card and see if the other Realtek
driver also has support for your card - if it does switch to that and try it. Do
you have a PCI slot and an old PCI ethernet card - if so try with that cabled up
instead of the Realtek PoS. Maybe try a live CD and see if that shares the
problem.

That lot sounds like a reasonable starting place...


--
Trevor Hemsley, Brighton, UK
Trevor dot Hemsley at ntlworld dot com

[Haines Brown]

"Trevor Hemsley" <Trevor....@mytrousers.ntlworld.com> writes:

> On Tue, 1 Nov 2011 18:15:45 UTC in comp.os.linux.hardware, Haines Brown
> <hai...@HistoricalMaterialism.info> wrote:
>
>> Are you implying that a faulty modem is a likely cause of cause of
>> reduced bandwidth? If so, I'll test by trying another modem. Is there
>> any way to test modem bandwidth?
>
> You said you had another machine - boot that and see what its throughput is
> like.

Thank you for the sequence of likely causes. As it turned out, I had my
grandson, who accesses my modem with wifi, check his connection speed,
and it was just as bad. So it looks like I'll have to dump the modem.

Haines

[Damiano Santini]

On 2 Nov, 14:30, Haines Brown <hai...@HistoricalMaterialism.info>
wrote:

You must see that the chipset Realtek 8168 are in pci-ex and 8169 in
pci. There is a bug and the kernel load driver r8169 also for the
r8168 with a lot of problems.
The r8168 drivers are for the follow NICs:
RTL8168B
RTL8168C
RTL8168CP
RTL8111B
RTL8111C
RTL8111CP

if your want know the NIC type :
lspci | grep Realtek

if is on the list make the follow:
1)download driver from
http://www.realtek.com/downloads/downloadsView.aspx?Langid=1&PNid=13&PFid=5&Level=5&Conn=4&DownTypeID=3&GetDown=false
2) execute as root
tar -xvf r8168-XXXXXXXXXX.tar.bz2
cd r8168-8.XXXXXXXXXXXX
make clean modules
make install
depmod -a
rmmod r8169
modprobe r8168

after edit file /etc/modprobe.d/blacklist
add line ' blacklist r8169'

after type:
update-initramfs -u
/etc/init.d/networking restart.

With right kernel module your NIC use all pci-ex resource(2,5 gb/s) in
real full duplex

[Curt]

On 2011-11-16, Damiano Santini <damy8...@yahoo.it> wrote:

> You must see that the chipset Realtek 8168 are in pci-ex and 8169 in
> pci. There is a bug and the kernel load driver r8169 also for the
> r8168 with a lot of problems.

I can confirm that (if I'm understanding what you're saying there).

curty@einstein:~$ lspci | grep -i ethernet
06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd.
RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)

curty@einstein:~$ uname -a
Linux einstein 2.6.32-5-amd64 #1 SMP Thu Nov 3 03:41:26 UTC 2011 x86_64
GNU/Linux

The kernel driver (r8169) is very flakey, with frequent connection
losses requiring restarting networking and poor throughput (is that the
correct term for diminished download speeds?).

> if is on the list make the follow:
> 1)download driver from
> http://www.realtek.com/downloads/downloadsView.aspx?Langid=1&PNid=13&PFid=5&Level=5&Conn=4&DownTypeID=3&GetDown=false

> 2) execute as root
> tar -xvf r8168-XXXXXXXXXX.tar.bz2
> cd r8168-8.XXXXXXXXXXXX

Why not use the autorun.sh script provided with the tarball?

> make clean modules
> make install
> depmod -a
> rmmod r8169
> modprobe r8168
>
> after edit file /etc/modprobe.d/blacklist
> add line ' blacklist r8169'

I don't have a file /etc/modprobe.d/blacklist.
I have /etc/modprobe.d/blacklist.conf

Using debian squeeze here. But the above file says "it does not affect
autoloading of modules by the kernel," so I wonder if your technique
would be effective. The autorun.sh script simply removes the module
('rmmod 8169', if it's loaded) and renames it r8169.bak.