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Very slow network - Ubuntu

 
 
A. Ben Hmeda
Guest
Posts: n/a

 
      03-17-2007, 06:34 PM
I have searched ubuntu forums to no avail. My network connection has
slowed down considerably since I installed Ubuntu Dapper (6.06.1 LTS) I
have disabled ipv6 in /etc/aliases and Firefox, still slow by about 50%.

My machine AMDSMP is dual boot w2k/ubuntu 6.06.1 LTS (2xAthlon 2000+ 512
RAM), network is at full speed with win2k and Fedora Core 5 (now
deleted) on this machine.

I have another Ubuntu 6.06.1 LTS machine SERVER (2xP3-500 256RAM) and a
Win2k KIDPC (P3-866 512RAM) on the same home network that do not have
this problem with the network slowdowns.

My benchmark is http://www.testmy.net/ website. Every machine on the
network has been tested separately, while other machines were turned off.

Didn't matter whether the connection was static or dhcp.
I have also noticed slowdowns (high latency) while playing on-line games
like bzflag
My /etc/network/interfaces :
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address 192.168.1.2
netmask 255.255.255.0
gateway 192.168.1.1

ifconfig output:

eth0 Link encap:Ethernet HWaddr 00:04:5A:9A:8C:6E
inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:46508 errors:0 dropped:0 overruns:0 frame:0
TX packets:31020 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:43829777 (41.7 MiB) TX bytes:4368831 (4.1 MiB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:9 errors:0 dropped:0 overruns:0 frame:0
TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:472 (472.0 b) TX bytes:472 (472.0 b)

What went wrong?
 
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CM
Guest
Posts: n/a

 
      03-17-2007, 07:46 PM
Just as a quick thought, have you tried swapping network cables and if
you have, have you tried plugging it into a different port on your router?



A. Ben Hmeda wrote:
> I have searched ubuntu forums to no avail. My network connection has
> slowed down considerably since I installed Ubuntu Dapper (6.06.1 LTS) I
> have disabled ipv6 in /etc/aliases and Firefox, still slow by about 50%.
>
> My machine AMDSMP is dual boot w2k/ubuntu 6.06.1 LTS (2xAthlon 2000+ 512
> RAM), network is at full speed with win2k and Fedora Core 5 (now
> deleted) on this machine.
>
> I have another Ubuntu 6.06.1 LTS machine SERVER (2xP3-500 256RAM) and a
> Win2k KIDPC (P3-866 512RAM) on the same home network that do not have
> this problem with the network slowdowns.
>
> My benchmark is http://www.testmy.net/ website. Every machine on the
> network has been tested separately, while other machines were turned off.
>
> Didn't matter whether the connection was static or dhcp.
> I have also noticed slowdowns (high latency) while playing on-line games
> like bzflag
> My /etc/network/interfaces :
> auto lo
> iface lo inet loopback
> auto eth0
> iface eth0 inet static
> address 192.168.1.2
> netmask 255.255.255.0
> gateway 192.168.1.1
>
> ifconfig output:
>
> eth0 Link encap:Ethernet HWaddr 00:04:5A:9A:8C:6E
> inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
> RX packets:46508 errors:0 dropped:0 overruns:0 frame:0
> TX packets:31020 errors:0 dropped:0 overruns:0 carrier:0
> collisions:0 txqueuelen:1000
> RX bytes:43829777 (41.7 MiB) TX bytes:4368831 (4.1 MiB)
>
> lo Link encap:Local Loopback
> inet addr:127.0.0.1 Mask:255.0.0.0
> UP LOOPBACK RUNNING MTU:16436 Metric:1
> RX packets:9 errors:0 dropped:0 overruns:0 frame:0
> TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
> collisions:0 txqueuelen:0
> RX bytes:472 (472.0 b) TX bytes:472 (472.0 b)
>
> What went wrong?

 
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Stefan Patric
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Posts: n/a

 
      03-17-2007, 10:07 PM
On Sat, 17 Mar 2007 15:34:47 -0400, A. Ben Hmeda wrote:

> I have searched ubuntu forums to no avail. My network connection has
> slowed down considerably since I installed Ubuntu Dapper (6.06.1 LTS) I
> have disabled ipv6 in /etc/aliases and Firefox, still slow by about 50%.
>
> My machine AMDSMP is dual boot w2k/ubuntu 6.06.1 LTS (2xAthlon 2000+ 512
> RAM), network is at full speed with win2k and Fedora Core 5 (now
> deleted) on this machine.
>
> I have another Ubuntu 6.06.1 LTS machine SERVER (2xP3-500 256RAM) and a
> Win2k KIDPC (P3-866 512RAM) on the same home network that do not have
> this problem with the network slowdowns.
>
> My benchmark is http://www.testmy.net/ website. Every machine on the
> network has been tested separately, while other machines were turned off.
>
> Didn't matter whether the connection was static or dhcp.
> I have also noticed slowdowns (high latency) while playing on-line games
> like bzflag
> My /etc/network/interfaces :
> auto lo
> iface lo inet loopback
> auto eth0
> iface eth0 inet static
> address 192.168.1.2
> netmask 255.255.255.0
> gateway 192.168.1.1
>
> ifconfig output:
>
> eth0 Link encap:Ethernet HWaddr 00:04:5A:9A:8C:6E
> inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
> RX packets:46508 errors:0 dropped:0 overruns:0 frame:0
> TX packets:31020 errors:0 dropped:0 overruns:0 carrier:0
> collisions:0 txqueuelen:1000
> RX bytes:43829777 (41.7 MiB) TX bytes:4368831 (4.1 MiB)
>
> lo Link encap:Local Loopback
> inet addr:127.0.0.1 Mask:255.0.0.0
> UP LOOPBACK RUNNING MTU:16436 Metric:1
> RX packets:9 errors:0 dropped:0 overruns:0 frame:0
> TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
> collisions:0 txqueuelen:0
> RX bytes:472 (472.0 b) TX bytes:472 (472.0 b)
>
> What went wrong?


You have a dual CPU machine. Have you checked to see if Ubuntu installed
an SMP kernel? Have you updated/upgraded your system, since the initial
install? What percentage is your CPU usage? man top for the details. If
it's more than a few percent or it's close to 100%, then I'd say you've
got a runaway process that's hogging the CPU and slowing everything down.

Have you checked your Ubuntu iso and CD burn for different checksums? You
may have a bad download or a bad burn or both. If you downloaded Ubuntu
on a Windows machine using IE, then you probably have a corrupted iso.
Use a dedicated ftp client, if you must download on a Windows machine. IE
does screwy things to Linux iso's when you use it to download.

If all of the above checks out as good. Just wipe the entire Ubuntu
install, do a badblocks check on the partitions, and reinstall it. Could
be a bad install. It happens.

Stef
 
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A. Ben Hmeda
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Posts: n/a

 
      03-17-2007, 10:15 PM
CM wrote:
> Just as a quick thought, have you tried swapping network cables and if
> you have, have you tried plugging it into a different port on your router?
>
>
>
> A. Ben Hmeda wrote:
>> I have searched ubuntu forums to no avail. My network connection has
>> slowed down considerably since I installed Ubuntu Dapper (6.06.1 LTS) I
>> have disabled ipv6 in /etc/aliases and Firefox, still slow by about 50%.
>>
>> My machine AMDSMP is dual boot w2k/ubuntu 6.06.1 LTS (2xAthlon 2000+ 512
>> RAM), network is at full speed with win2k and Fedora Core 5 (now
>> deleted) on this machine.
>>
>> I have another Ubuntu 6.06.1 LTS machine SERVER (2xP3-500 256RAM) and a
>> Win2k KIDPC (P3-866 512RAM) on the same home network that do not have
>> this problem with the network slowdowns.
>>
>> My benchmark is http://www.testmy.net/ website. Every machine on the
>> network has been tested separately, while other machines were turned off.
>>
>> Didn't matter whether the connection was static or dhcp.
>> I have also noticed slowdowns (high latency) while playing on-line games
>> like bzflag
>> My /etc/network/interfaces :
>> auto lo
>> iface lo inet loopback
>> auto eth0
>> iface eth0 inet static
>> address 192.168.1.2
>> netmask 255.255.255.0
>> gateway 192.168.1.1
>>
>> ifconfig output:
>>
>> eth0 Link encap:Ethernet HWaddr 00:04:5A:9A:8C:6E
>> inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
>> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
>> RX packets:46508 errors:0 dropped:0 overruns:0 frame:0
>> TX packets:31020 errors:0 dropped:0 overruns:0 carrier:0
>> collisions:0 txqueuelen:1000
>> RX bytes:43829777 (41.7 MiB) TX bytes:4368831 (4.1 MiB)
>>
>> lo Link encap:Local Loopback
>> inet addr:127.0.0.1 Mask:255.0.0.0
>> UP LOOPBACK RUNNING MTU:16436 Metric:1
>> RX packets:9 errors:0 dropped:0 overruns:0 frame:0
>> TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
>> collisions:0 txqueuelen:0
>> RX bytes:472 (472.0 b) TX bytes:472 (472.0 b)
>>
>> What went wrong?


No I have not. As I mentioned, network is as fast as it can be under
win2k and Fedora5 (on the same machine) it is just when I boot into
Ubuntu, it slows right down.

As I was trying to figure this out, I noticed that network speed is
drastically improved under Ubuntu when I open the
System>>Administration>>Networking and just click OK, without actually
changing anything! This makes no sense to me and I have no explanation
for it, it certainly does not change the content in my
/etc/network/interfaces but I was able to duplicate the steps with same
results every time.
 
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A. Ben Hmeda
Guest
Posts: n/a

 
      03-17-2007, 10:21 PM
Stefan Patric wrote:
> On Sat, 17 Mar 2007 15:34:47 -0400, A. Ben Hmeda wrote:
>
>> I have searched ubuntu forums to no avail. My network connection has
>> slowed down considerably since I installed Ubuntu Dapper (6.06.1 LTS) I
>> have disabled ipv6 in /etc/aliases and Firefox, still slow by about 50%.
>>
>> My machine AMDSMP is dual boot w2k/ubuntu 6.06.1 LTS (2xAthlon 2000+ 512
>> RAM), network is at full speed with win2k and Fedora Core 5 (now
>> deleted) on this machine.
>>
>> I have another Ubuntu 6.06.1 LTS machine SERVER (2xP3-500 256RAM) and a
>> Win2k KIDPC (P3-866 512RAM) on the same home network that do not have
>> this problem with the network slowdowns.
>>
>> My benchmark is http://www.testmy.net/ website. Every machine on the
>> network has been tested separately, while other machines were turned off.
>>
>> Didn't matter whether the connection was static or dhcp.
>> I have also noticed slowdowns (high latency) while playing on-line games
>> like bzflag
>> My /etc/network/interfaces :
>> auto lo
>> iface lo inet loopback
>> auto eth0
>> iface eth0 inet static
>> address 192.168.1.2
>> netmask 255.255.255.0
>> gateway 192.168.1.1
>>
>> ifconfig output:
>>
>> eth0 Link encap:Ethernet HWaddr 00:04:5A:9A:8C:6E
>> inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
>> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
>> RX packets:46508 errors:0 dropped:0 overruns:0 frame:0
>> TX packets:31020 errors:0 dropped:0 overruns:0 carrier:0
>> collisions:0 txqueuelen:1000
>> RX bytes:43829777 (41.7 MiB) TX bytes:4368831 (4.1 MiB)
>>
>> lo Link encap:Local Loopback
>> inet addr:127.0.0.1 Mask:255.0.0.0
>> UP LOOPBACK RUNNING MTU:16436 Metric:1
>> RX packets:9 errors:0 dropped:0 overruns:0 frame:0
>> TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
>> collisions:0 txqueuelen:0
>> RX bytes:472 (472.0 b) TX bytes:472 (472.0 b)
>>
>> What went wrong?

>
> You have a dual CPU machine. Have you checked to see if Ubuntu installed
> an SMP kernel? Have you updated/upgraded your system, since the initial
> install? What percentage is your CPU usage? man top for the details. If
> it's more than a few percent or it's close to 100%, then I'd say you've
> got a runaway process that's hogging the CPU and slowing everything down.
>
> Have you checked your Ubuntu iso and CD burn for different checksums? You
> may have a bad download or a bad burn or both. If you downloaded Ubuntu
> on a Windows machine using IE, then you probably have a corrupted iso.
> Use a dedicated ftp client, if you must download on a Windows machine. IE
> does screwy things to Linux iso's when you use it to download.
>
> If all of the above checks out as good. Just wipe the entire Ubuntu
> install, do a badblocks check on the partitions, and reinstall it. Could
> be a bad install. It happens.
>
> Stef


Answering your questions:
I fetched the smp kernel from the ubuntu archives myself
The system is fully patched to dapper-security
no runaway processes
I received the CDs by mail from ubuntu.com
As for the screwy stuff, please see my reply to CM
Thanks
 
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Stefan Patric
Guest
Posts: n/a

 
      03-18-2007, 09:14 PM
On Sat, 17 Mar 2007 19:21:10 -0400, A. Ben Hmeda wrote:

> Stefan Patric wrote:
>> On Sat, 17 Mar 2007 15:34:47 -0400, A. Ben Hmeda wrote:
>>
>>> I have searched ubuntu forums to no avail. My network connection has
>>> slowed down considerably since I installed Ubuntu Dapper (6.06.1 LTS) I
>>> have disabled ipv6 in /etc/aliases and Firefox, still slow by about 50%.
>>>
>>> My machine AMDSMP is dual boot w2k/ubuntu 6.06.1 LTS (2xAthlon 2000+ 512
>>> RAM), network is at full speed with win2k and Fedora Core 5 (now
>>> deleted) on this machine.
>>>
>>> I have another Ubuntu 6.06.1 LTS machine SERVER (2xP3-500 256RAM) and a
>>> Win2k KIDPC (P3-866 512RAM) on the same home network that do not have
>>> this problem with the network slowdowns.
>>>
>>> My benchmark is http://www.testmy.net/ website. Every machine on the
>>> network has been tested separately, while other machines were turned off.
>>>
>>> Didn't matter whether the connection was static or dhcp.
>>> I have also noticed slowdowns (high latency) while playing on-line games
>>> like bzflag
>>> My /etc/network/interfaces :
>>> auto lo
>>> iface lo inet loopback
>>> auto eth0
>>> iface eth0 inet static
>>> address 192.168.1.2
>>> netmask 255.255.255.0
>>> gateway 192.168.1.1
>>>
>>> ifconfig output:
>>>
>>> eth0 Link encap:Ethernet HWaddr 00:04:5A:9A:8C:6E
>>> inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
>>> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
>>> RX packets:46508 errors:0 dropped:0 overruns:0 frame:0
>>> TX packets:31020 errors:0 dropped:0 overruns:0 carrier:0
>>> collisions:0 txqueuelen:1000
>>> RX bytes:43829777 (41.7 MiB) TX bytes:4368831 (4.1 MiB)
>>>
>>> lo Link encap:Local Loopback
>>> inet addr:127.0.0.1 Mask:255.0.0.0
>>> UP LOOPBACK RUNNING MTU:16436 Metric:1
>>> RX packets:9 errors:0 dropped:0 overruns:0 frame:0
>>> TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
>>> collisions:0 txqueuelen:0
>>> RX bytes:472 (472.0 b) TX bytes:472 (472.0 b)
>>>
>>> What went wrong?

>>
>> You have a dual CPU machine. Have you checked to see if Ubuntu installed
>> an SMP kernel? Have you updated/upgraded your system, since the initial
>> install? What percentage is your CPU usage? man top for the details. If
>> it's more than a few percent or it's close to 100%, then I'd say you've
>> got a runaway process that's hogging the CPU and slowing everything down.
>>
>> Have you checked your Ubuntu iso and CD burn for different checksums? You
>> may have a bad download or a bad burn or both. If you downloaded Ubuntu
>> on a Windows machine using IE, then you probably have a corrupted iso.
>> Use a dedicated ftp client, if you must download on a Windows machine. IE
>> does screwy things to Linux iso's when you use it to download.
>>
>> If all of the above checks out as good. Just wipe the entire Ubuntu
>> install, do a badblocks check on the partitions, and reinstall it. Could
>> be a bad install. It happens.
>>
>> Stef

>
> Answering your questions:
> I fetched the smp kernel from the ubuntu archives myself
> The system is fully patched to dapper-security
> no runaway processes
> I received the CDs by mail from ubuntu.com
> As for the screwy stuff, please see my reply to CM
> Thanks


I read your reply to CM (quoted below). Yes, that is strange, but not
unheard of. (I had a similar thing some years ago with Slackware and
CUPS. Printing wouldn't work until you open CUPS' html config
interface,selected administer printers, select the printer -- there was
only one -- and save without changing anything, then printing worked
until you rebooted. Then you had to do it all over, again. All the
config files were correctly set up.

Anyway, with your system, this suggests to me that something IS wrong
with your install. Or you could have a bad CD. Or something was changed
when you update/upgraded and/or installed the SMP kernel. Try installing
Ubuntu from the purchased CD on a new partition without erasing the old
install. Go through the whole upgrade thing and see if you have the same
problem.

Personally, I'd download 6.10 and burn my own CD, then I'd know at least
that was without errors.

Good luck....

Stef

================================================== ==================
Reply to CM [snipped]

As I was trying to figure this out, I noticed that network speed is
drastically improved under Ubuntu when I open the
System>>Administration>>Networking and just click OK, without actually
changing anything! This makes no sense to me and I have no explanation
for it, it certainly does not change the content in my
/etc/network/interfaces but I was able to duplicate the steps with same
results every time.

================================================== ===================
 
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A. Ben Hmeda
Guest
Posts: n/a

 
      03-19-2007, 02:19 AM
Stefan Patric wrote:
> On Sat, 17 Mar 2007 19:21:10 -0400, A. Ben Hmeda wrote:
>
>> Stefan Patric wrote:
>>> On Sat, 17 Mar 2007 15:34:47 -0400, A. Ben Hmeda wrote:
>>>
>>>> I have searched ubuntu forums to no avail. My network connection has
>>>> slowed down considerably since I installed Ubuntu Dapper (6.06.1 LTS) I
>>>> have disabled ipv6 in /etc/aliases and Firefox, still slow by about 50%.
>>>>
>>>> My machine AMDSMP is dual boot w2k/ubuntu 6.06.1 LTS (2xAthlon 2000+ 512
>>>> RAM), network is at full speed with win2k and Fedora Core 5 (now
>>>> deleted) on this machine.
>>>>
>>>> I have another Ubuntu 6.06.1 LTS machine SERVER (2xP3-500 256RAM) and a
>>>> Win2k KIDPC (P3-866 512RAM) on the same home network that do not have
>>>> this problem with the network slowdowns.
>>>>
>>>> My benchmark is http://www.testmy.net/ website. Every machine on the
>>>> network has been tested separately, while other machines were turned off.
>>>>
>>>> Didn't matter whether the connection was static or dhcp.
>>>> I have also noticed slowdowns (high latency) while playing on-line games
>>>> like bzflag
>>>> My /etc/network/interfaces :
>>>> auto lo
>>>> iface lo inet loopback
>>>> auto eth0
>>>> iface eth0 inet static
>>>> address 192.168.1.2
>>>> netmask 255.255.255.0
>>>> gateway 192.168.1.1
>>>>
>>>> ifconfig output:
>>>>
>>>> eth0 Link encap:Ethernet HWaddr 00:04:5A:9A:8C:6E
>>>> inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
>>>> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
>>>> RX packets:46508 errors:0 dropped:0 overruns:0 frame:0
>>>> TX packets:31020 errors:0 dropped:0 overruns:0 carrier:0
>>>> collisions:0 txqueuelen:1000
>>>> RX bytes:43829777 (41.7 MiB) TX bytes:4368831 (4.1 MiB)
>>>>
>>>> lo Link encap:Local Loopback
>>>> inet addr:127.0.0.1 Mask:255.0.0.0
>>>> UP LOOPBACK RUNNING MTU:16436 Metric:1
>>>> RX packets:9 errors:0 dropped:0 overruns:0 frame:0
>>>> TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
>>>> collisions:0 txqueuelen:0
>>>> RX bytes:472 (472.0 b) TX bytes:472 (472.0 b)
>>>>
>>>> What went wrong?
>>> You have a dual CPU machine. Have you checked to see if Ubuntu installed
>>> an SMP kernel? Have you updated/upgraded your system, since the initial
>>> install? What percentage is your CPU usage? man top for the details. If
>>> it's more than a few percent or it's close to 100%, then I'd say you've
>>> got a runaway process that's hogging the CPU and slowing everything down.
>>>
>>> Have you checked your Ubuntu iso and CD burn for different checksums? You
>>> may have a bad download or a bad burn or both. If you downloaded Ubuntu
>>> on a Windows machine using IE, then you probably have a corrupted iso.
>>> Use a dedicated ftp client, if you must download on a Windows machine. IE
>>> does screwy things to Linux iso's when you use it to download.
>>>
>>> If all of the above checks out as good. Just wipe the entire Ubuntu
>>> install, do a badblocks check on the partitions, and reinstall it. Could
>>> be a bad install. It happens.
>>>
>>> Stef

>> Answering your questions:
>> I fetched the smp kernel from the ubuntu archives myself
>> The system is fully patched to dapper-security
>> no runaway processes
>> I received the CDs by mail from ubuntu.com
>> As for the screwy stuff, please see my reply to CM
>> Thanks

>
> I read your reply to CM (quoted below). Yes, that is strange, but not
> unheard of. (I had a similar thing some years ago with Slackware and
> CUPS. Printing wouldn't work until you open CUPS' html config
> interface,selected administer printers, select the printer -- there was
> only one -- and save without changing anything, then printing worked
> until you rebooted. Then you had to do it all over, again. All the
> config files were correctly set up.
>
> Anyway, with your system, this suggests to me that something IS wrong
> with your install. Or you could have a bad CD. Or something was changed
> when you update/upgraded and/or installed the SMP kernel. Try installing
> Ubuntu from the purchased CD on a new partition without erasing the old
> install. Go through the whole upgrade thing and see if you have the same
> problem.
>
> Personally, I'd download 6.10 and burn my own CD, then I'd know at least
> that was without errors.
>
> Good luck....
>
> Stef
>
> ================================================== ==================
> Reply to CM [snipped]
>
> As I was trying to figure this out, I noticed that network speed is
> drastically improved under Ubuntu when I open the
> System>>Administration>>Networking and just click OK, without actually
> changing anything! This makes no sense to me and I have no explanation
> for it, it certainly does not change the content in my
> /etc/network/interfaces but I was able to duplicate the steps with same
> results every time.
>
> ================================================== ===================


I might just do that. Thank you all.
 
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Rick Jones
Guest
Posts: n/a

 
      03-19-2007, 04:33 PM
A partial list of things to check, not necessarily in any order:

*) packet losses - check that netstat and ethtool stats are "clean"

*) TCP window sizes

*) firewall settings

*) whether or not net.ipv4.tcp_abc is set (if you have apps making
lots of small sends)

rick jones
--
firebug n, the idiot who tosses a lit cigarette out his car window
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
 
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A. Ben Hmeda
Guest
Posts: n/a

 
      04-08-2007, 06:41 PM
Stefan Patric wrote:
> On Sat, 17 Mar 2007 19:21:10 -0400, A. Ben Hmeda wrote:
>
>> Stefan Patric wrote:
>>> On Sat, 17 Mar 2007 15:34:47 -0400, A. Ben Hmeda wrote:
>>>
>>>> I have searched ubuntu forums to no avail. My network connection has
>>>> slowed down considerably since I installed Ubuntu Dapper (6.06.1 LTS) I
>>>> have disabled ipv6 in /etc/aliases and Firefox, still slow by about 50%.
>>>>
>>>> My machine AMDSMP is dual boot w2k/ubuntu 6.06.1 LTS (2xAthlon 2000+ 512
>>>> RAM), network is at full speed with win2k and Fedora Core 5 (now
>>>> deleted) on this machine.
>>>>
>>>> I have another Ubuntu 6.06.1 LTS machine SERVER (2xP3-500 256RAM) and a
>>>> Win2k KIDPC (P3-866 512RAM) on the same home network that do not have
>>>> this problem with the network slowdowns.
>>>>
>>>> My benchmark is http://www.testmy.net/ website. Every machine on the
>>>> network has been tested separately, while other machines were turned off.
>>>>
>>>> Didn't matter whether the connection was static or dhcp.
>>>> I have also noticed slowdowns (high latency) while playing on-line games
>>>> like bzflag
>>>> My /etc/network/interfaces :
>>>> auto lo
>>>> iface lo inet loopback
>>>> auto eth0
>>>> iface eth0 inet static
>>>> address 192.168.1.2
>>>> netmask 255.255.255.0
>>>> gateway 192.168.1.1
>>>>
>>>> ifconfig output:
>>>>
>>>> eth0 Link encap:Ethernet HWaddr 00:04:5A:9A:8C:6E
>>>> inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
>>>> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
>>>> RX packets:46508 errors:0 dropped:0 overruns:0 frame:0
>>>> TX packets:31020 errors:0 dropped:0 overruns:0 carrier:0
>>>> collisions:0 txqueuelen:1000
>>>> RX bytes:43829777 (41.7 MiB) TX bytes:4368831 (4.1 MiB)
>>>>
>>>> lo Link encap:Local Loopback
>>>> inet addr:127.0.0.1 Mask:255.0.0.0
>>>> UP LOOPBACK RUNNING MTU:16436 Metric:1
>>>> RX packets:9 errors:0 dropped:0 overruns:0 frame:0
>>>> TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
>>>> collisions:0 txqueuelen:0
>>>> RX bytes:472 (472.0 b) TX bytes:472 (472.0 b)
>>>>
>>>> What went wrong?
>>> You have a dual CPU machine. Have you checked to see if Ubuntu installed
>>> an SMP kernel? Have you updated/upgraded your system, since the initial
>>> install? What percentage is your CPU usage? man top for the details. If
>>> it's more than a few percent or it's close to 100%, then I'd say you've
>>> got a runaway process that's hogging the CPU and slowing everything down.
>>>
>>> Have you checked your Ubuntu iso and CD burn for different checksums? You
>>> may have a bad download or a bad burn or both. If you downloaded Ubuntu
>>> on a Windows machine using IE, then you probably have a corrupted iso.
>>> Use a dedicated ftp client, if you must download on a Windows machine. IE
>>> does screwy things to Linux iso's when you use it to download.
>>>
>>> If all of the above checks out as good. Just wipe the entire Ubuntu
>>> install, do a badblocks check on the partitions, and reinstall it. Could
>>> be a bad install. It happens.
>>>
>>> Stef

>> Answering your questions:
>> I fetched the smp kernel from the ubuntu archives myself
>> The system is fully patched to dapper-security
>> no runaway processes
>> I received the CDs by mail from ubuntu.com
>> As for the screwy stuff, please see my reply to CM
>> Thanks

>
> I read your reply to CM (quoted below). Yes, that is strange, but not
> unheard of. (I had a similar thing some years ago with Slackware and
> CUPS. Printing wouldn't work until you open CUPS' html config
> interface,selected administer printers, select the printer -- there was
> only one -- and save without changing anything, then printing worked
> until you rebooted. Then you had to do it all over, again. All the
> config files were correctly set up.
>
> Anyway, with your system, this suggests to me that something IS wrong
> with your install. Or you could have a bad CD. Or something was changed
> when you update/upgraded and/or installed the SMP kernel. Try installing
> Ubuntu from the purchased CD on a new partition without erasing the old
> install. Go through the whole upgrade thing and see if you have the same
> problem.
>
> Personally, I'd download 6.10 and burn my own CD, then I'd know at least
> that was without errors.
>
> Good luck....
>
> Stef
>
> ================================================== ==================
> Reply to CM [snipped]
>
> As I was trying to figure this out, I noticed that network speed is
> drastically improved under Ubuntu when I open the
> System>>Administration>>Networking and just click OK, without actually
> changing anything! This makes no sense to me and I have no explanation
> for it, it certainly does not change the content in my
> /etc/network/interfaces but I was able to duplicate the steps with same
> results every time.
>
> ================================================== ===================


FWIW, I have clean-installed Edgy (Ubuntu 6.10) and found that the
problem is still there. I still had to issue /etc/init.d/networking
restart after my system has booted otherwise my network connection
crawls at 15kB to 45kB (max) vs. 90kB to 120 kB. I'm back to 6.06.1 LTS
because Canonical is issuing security updates for it until 2009 (2011
for servers).
 
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