download speed machine dependant? [Archive]

Doom9

8th February 2006, 10:29

Obviously that question makes no sense (well.. there are migitating circumstances like really bad network drivers, etc.. but none of that would apply here).
For months now, my FTP connection to one of my site servers is behaving strangely. Upload speeds are in order, but I noted that directory listing is dead slow. So I experimented a little and found out that for some reason that is way beyond me, my download speed (which directory listing is based on) from that particular site server fluctuates between absymally low (like 1 KB/s), to slow (20 KB/s).. way below the capacity of my line and even my upload speed. Going via HTTP speeds up things a little, but not by much. At first I figured it's my ISP. Then however, by chance one evening I used my notebook from work at home and interestingly enough, it did not exhibit the same problem.. download via http and ftp went at full blast. So I figured it would be a weird time coincidence, started my own box, but that once again was going slow. Downloading simultaneously also show that picture: my own box is slow, the notebook goes fast. So I figured, it must by my box, something weird in the installation (which is at times acting weird). I recently got a new HD so I installed Windows on the new HD and booted up from it, and ran another test. Once again, the same behavior. Then finally I tried the other box that I don't normally use, and once again I saw the same behavior. I also found out that if the traffic is redirected by a third party, then download speed is in order for all three machines.

Knowing that there's no way to make the difference between different machines behind a NAT, it can't be that somebody would "recognize" my machine and slow me down.. so the problem must be in-house. And this one server is the only machine on the net where I've ever been able to see such behavior. So I'm wondering, what on earth could make two machines pull the handbrake in this particular case and another one acting like it should?

Doom9

8th February 2006, 21:55

even from a virtual machine installed on that notebook.. still the same thing.. I just don't get it.

zilog jones

8th February 2006, 22:41

This sounds quite weird.

Are there any set-up differences between your PCs? Are they all the same OSes (and same service packs), and do they have their own software firewalls? Are they all connected to your router/modem in the same way?

For a second I was thinking it could be hard-disk related, but there'd have to be some seriously chronic fragmentation (or something really dodgy going on) for HDD transfer speeds to be that slow...

You sure there's nothing else using up all your CPU cycles or hogging your bandwidth while you're downloading on the apparently slower PC? Then again the chances of a similar situation happening on a fresh install would be very odd.

Is there any sort of management on your router or NIC... wait, that wouldn't make sense for just one particular server either...

OK. I give up!

*.mp4 guy

8th February 2006, 22:44

Do they all use the same firewall software? what about browsers? Some motherboard manufacturers have hardware firewalls built into there etherenet conections so you might want to check that. Also how is your network configured (for instance does the laptop use wireless while your other computers use ethernet?). It could also be your router(s) doing traffic shaping, if your router detects high latency it will drop packets to lower the datarate and improve latency, your router may be configured to do this for the computers you usually have around, but not for your laptop. It may ony be effecting this server because because it is sending data through a congested insternational pipe, so your isp could be using cuing to improve your datarate, which would give you bad latency(which would cause your router to start doing traffic shaping).

First I would try taking your router out of the equation and seeying if the problem persist when you connect your computer directly to your internet connection.

Doom9

9th February 2006, 00:09

It could also be your router(s) doing traffic shapingIf it were something on the router I'd know.. plus when I set up two VMs on the notebook that has no problem, and they both had the slowdowns going out via the same NIC, that pretty much rules that out as well. And naturally I've considered firewalls (and deactivated them just in case). OSes tried are XP Pro, MCE2005 and W2k3 server.
And you can't take out the router since it contains the DSL modem.. and that router has no way of limiting traffic for a particular MAC address.. and as I said.. VMS via the computer that acts as it should also get slowed down..

Revgen

9th February 2006, 02:10

Just a few ideas.

1) Could it be spyware or viruses?

2) Could it be your registry settings? There are registry settings that control packet flow.

3) Is your next-door neighbor tapping your line?:D

Shinigami-Sama

9th February 2006, 05:43

I set up two VMs on the notebook that has no problem, and they both had the slowdowns going out via the same NIC
swap the nic out?

Doom9

9th February 2006, 09:18

swap the nic out?In a notebook? Yeah right. If I run VMs on that notebook it can't be the card ;)

@revgen: 1) no that can be categorically ruled out (it happens with a fresh install right off the original CDs from MSDN.. I have a hardware firewall that blocks any incoming connections and no software whatsoever was installed.. it's just install windows and try.. I repeated that procedure 3 times yesterday
2) like what? keep in mind... it's just one site and only for the download, upload is fine
3)no (that also couldn't explain it.. once again.. just one site, and just download)

Inventive Software

9th February 2006, 12:24

If the machine you're downloading from is quite slow (i.e. Pentium I or something similar) then the machine might hinder the download performance. However, you have the same problem when you use a Virtual Machine on your notebook.

????????????????

Sounds like a bandwidth issue or something similar. What OS are you running?

just one site, and just download
Does it happen continually with the same site? Or does it happen with other sites where you download stuff as well? I have had problems with too many connections to a particular website slowing down the download speed. Having a lot of users connected with the ISP can slow things down as well, as there is less bandwidth for each connection.

Doom9

9th February 2006, 12:36

If the machine you're downloading from is quite slowWell.. then every download would have to be slow.. this clearly isn't the case.
What OS are you running?I tried XP Pro SP2, MCE2005 and W2k3 Server SP1.. so rule out the OS. Also rule out any configuration on those machines since some tests were done in brand new setups (and access to any other site from these machines delivers the usual speed)
Does it happen continually with the same site? Like clockwork.. it doesn't vary at all. And I can have two sessions concurrently, one from my PC one from my notebook.. the one from my notebook gets good speed, the other abysmal.. if I then stop the notebook, nothing changes.
And I think I already mentioned we can rule out the ISP and the path... nobody can discern if the connection is initiated by my notebook or by my regular box. That means the problem is local and it comes down to "how can download (and not upload!!! upload goes at full speed from all machines) to one single site by severely degraded from all but one machine in the same network when those machines use different hardware, different operating systems and no configuration but a basic windows setup (software as it is on the CD.. I made tests even prior to installing the first patch).

I don't think it's a thing of having anything enabled on the notebook.. download speed just dropped from one day to another on my other box without making any changes to neither router or the machines themselves.

dragongodz

9th February 2006, 13:14

i would reccomend checking the hidden internet settings such as TTL etc. i found i had to increase that(to 64 over default 32) recently to fix some problems with some sites.

a lot of all in 1 tweaking programs should have the ability to do that but if you dont have such a thing then you could try something like this little freeware program
http://www.majorgeeks.com/CyberTweak_d2351.html

so check that all settings are the same for both the notebook and your box. if any are different then change them accordingly and reboot and retry etc.

Doom9

9th February 2006, 13:31

so check that all settings are the same for both the notebook and your box.They are all at their default values. If TTL32 doesn't do it for you, then those sites are really far away.. the site in question is just 15 hops away (actually 14.. the router acts as a double hop)

dragongodz

9th February 2006, 15:38

If TTL32 doesn't do it for you, then those sites are really far away
actually in my case it was pain the the #@$# isps that had a heap of hops amongst themselves. about 7 or 8 here and then another 5 or 6 on the other end alone. so the total getting from point a to b did just go over 32. while going to a different isp in the same city had less hops. :)

They are all at their default values.
the problem is that you said
when I set up two VMs on the notebook that has no problem, and they both had the slowdowns going out via the same NIC,
that suggests there is a setting, whether for net or hardware, that is different. the only way you are going to find it is to go through everything 1 at a time.

Doom9

9th February 2006, 15:41

keep in mind that as far as windows in the vm is concerned, it's a different piece of hardware though.. and as far as the host is concerned, the sample applies.. there's a new network interface (actually two) when you install vmware.

dragongodz

9th February 2006, 15:53

of course which is why i also said hardware settings may be different. however since
I also found out that if the traffic is redirected by a third party, then download speed is in order for all three machines.
that would suggest its less likely to be hardware settings related. thats why i said checking TTL, MTU etc would be the first things i would check to make sure they were all exactly the same. if they are all still defaults then its going to be really hard to find i guess.

Doom9

9th February 2006, 16:04

if they are all still defaults then its going to be really hard to find i guess.I already posted that they are all on their default settings (yes, I downloaded the tool you mentioned and checked.. I even checked the registry just to make sure).

johnhamler1

9th February 2006, 16:14

window limit to 10 connections.why it is so slow...

Doom9

9th February 2006, 17:05

window limit to 10 connections.why it is so slow...I think I know what you're getting at but that's a P2P issue. Since the same number of connections to any other site do not result in a slowdown, this cannot be it.

zilog jones

9th February 2006, 20:50

Can't you change the NIC in the PC you're getting this slowdown with? Or is that a notebook too?

Also, have you tried using one of your PCs as a gateway to your problem PC? i.e. install 2 NICs into one of your other PCs, connect one NIC to your router/modem/whatever and then connect the other NIC to the PC with the weird problem, and use Windows Internet Connection Sharing to make it act like a router.

Also, it probably won't make any difference but have you tried Linux or some other non-MS OS?

Doom9

9th February 2006, 20:59

Can't you change the NIC in the PC you're getting this slowdown with? Or is that a notebook too?Two physical PCs, and two virtual machines (then I gave up setting them up) on the notebook that has no problem.. safe to say it's not the hardware.
Also, have you tried using one of your PCs as a gateway to your problem PC?You're misreading.. there's one machine that has no problem and 4 that have it.. I'm pretty confident that any other machines I set up have the problem as well.
I already tried 3 operating systems.. another one isn't gonna change anything.. a MS OS has no issue either. And no Linux is going to make it onto my box.. half my hardware wouldn't work anyway.

Inventive Software

9th February 2006, 21:17

OK, this is getting weirder the more I read it. Can I make 1 point first? Live CDs are a great Linux resource, and make no changes whatsoever. ;)

Since you've ruled out any hardware discrepencies, the problem must be a software one... You've tried several OS's, all of which are relatively new. I take it you didn't try 98 or any older-than XP OS's, as it appears they (the OS's you tried) are all based around NT, loosely.

All configurations in new operating systems are different. Make sure the settings that work for your notebook are mostly similar for the box you're trying to get working. This includes your modem or NIC settings.

Other than that, it may be a case of IP targeting, where if a certain IP or IP range logs in to the site, then the bandwidth is throttled. Just a thought.

zilog jones

9th February 2006, 21:21

I certainly am mis-reading...

MaximRecoil

9th February 2006, 22:25

Let me see if I can sum this up. Your machine which is behind a NAT router/modem all of the sudden started to download via FTP from one server slowly. You tried a different PC with the same results. Your laptop from work, when connected to the same router/modem at home downloaded full speed from the server. Is that about right?

I would start by eliminating a few things from the equation. For one, get rid of the NAT. I don't know what you have for a modem, but most of them will allow you to set it to "bridged" aka "ip passthrough" mode, which completely disables its NAT functions and makes it into a straight modem. This will give your NIC a "real" WAN IP address. If your connection is PPPoE then you will need to set up a manual connection (Network Connections > File > New Connection > Next > Connect to the Internet > Set up my connection manually > Connect using a broadband connection that requires a user name and password). If your ISP uses DHCP, then you will get an IP address and connection automatically upon reboot of your PC or CMD > ipconfig /release > ipconfig /renew.

I would see what happens at that point first, and then I would try either installing Win2K, using a Live Linux CD, or a BartPE disc with the "OffByOne" browser added.

Also, you have a great forum here but your issue really isn't its specialty. Try posting your question on a more specialized computer forum such as http://board.iexbeta.com

Doom9

9th February 2006, 23:37

Live CDs are a great Linux resourceEspecially great if they support your NIC and GFX card. That also goes for BartPE by the way.. and having tried 4 different machines, 5 different installations and 3 different operating systems.. I'm about done with those experiments.
where if a certain IP or IP range logs in to the site, then the bandwidth is throttled. NAT to the rescue.. it doesn't matter where I download from.. the external IP is the same ;)
Is that about right?That's exactly right.
For one, get rid of the NAT. That doesn't make any sense since the device that acts normally is also behind the same NAT. For the fun of it, I even took the IP normally assigned (DHCP) to my regular PC and gave it to my notebook to make sure it's not some weird IP problem in my home network.

MaximRecoil

10th February 2006, 00:08

That doesn't make any sense since the device that acts normally is also behind the same NAT. For the fun of it, I even took the IP normally assigned (DHCP) to my regular PC and gave it to my notebook to make sure it's not some weird IP problem in my home network.It doesn't have to make sense! You know, since I've been dealing with and working with/on computers, I think I have begun to believe in "curses" or something. I've seen weird software issues appear out of the blue and actually stick around after a complete reformat and reinstall. I have a friend who gets slow P2P downloads no matter what, and has for years. He is a network administrator and knows his stuff. I have long since given up on that issue and have chalked it up to a "curse", lol. And that curse follows him around through various PC's, OS's, residences, P2P software and ISP's he's gone through since I have known him.

But yeah, I realize that the laptop that gets full speed is also behind the same NAT when doing so, but I would still start there, especially since it seems to be pretty much the only constant (you've tried other PC's and other OS's and pretty much changed everything around but that NAT has remained the same).

The problem is either esoteric or it is staring you square in the face. Either way, I would kick the NAT to the curb and go from there.

mpucoder

10th February 2006, 04:17

It could be the router ports, or the speed of the connected NICs - are they all 10, 100, or 1000 Mbps?

MaximRecoil

10th February 2006, 04:34

It could be the router ports, or the speed of the connected NICs - are they all 10, 100, or 1000 Mbps?Even a 10 Mbps NIC or router port wouldn't throttle a connection down to 10 or 20 KB/s. 10 Mbps = 1.25 MB/s = 1280 KB/s.

He also said that he still gets full upload speed :-/

Very strange. It would be a lot easier to figure out if it wasn't for that damnable laptop of his that gets full DL speed, being part of the equation.

Doom9

10th February 2006, 09:11

It could be the router portsThey're all connected to the same switch... and the VM from the notebook goes to the same switch port as the notebook itself.
I have three things on my todo list: factory reset the router, run ethereal for a good and bad connection on both ends and see if there's any difference (look at TCP exchanges.. see how tx/rx windows behave and if there's considerable packet loss (very unlikely)), and put a wlan nic into the notebook (the router also has wlan.. but it's shut down).

Doom9

14th February 2006, 12:55

well.. Knopix sure doesnt want to give me the keyboard layout I want. Regardless, I did some testing and its weird: I downloaded two large files via commandline ftp, and the app reported normal speed. Then I tried another download from the browser (Firefox of course), and this time I get below 30 KB/s (so not good.. but not abysmal either).

Doom9

14th February 2006, 17:00

Well, with the above we can rule out hardware. So as an additional test, I tried ftp from the commandline instead of my usual ftp client (flashfxp), and guess what, it goes at full speed, too. So, in addition to ruling out the hardware, I can now also rule out the operating system. That leaves the ftp client. So I went and compared settings, knowing that commandline ftp uses active mode. And passive mode is the default for most other ftp software. And in comparing the site setup on my notebook and my PC I finally found what I've been looking for: when I get rid of passive mode, the speed is finally in order again.
So then the question remains: how can the use of passive mode slow things down this dramatically?

Shinigami-Sama

14th February 2006, 17:38

some servers don't like passive and some don't like active, it's a bit of a pain in the ass, but it's all in the settings, I find it odd, but thats whats nice about a client that lets you choose

lexor

14th February 2006, 19:41

well this isn't exactly what I had in terms of symptoms, but result sounds similar, so I guess it's worth a try:

What I had is perfectly normal internet speed, but my pc-to-pc transfer was dismal (like 10kbps) on a LAN, this turned out to be an issue with lan settings, namely I had them forced to 10Mbps which is what my router and NICs support, so I thought that's a good thing to just tell it what to do. But nooo, aparently that's not good enough, and setting each machine to Autoresolve the speed fixed the problem.

also are all transfers you start use the same (for ftp default) port? or do you have some clients on differnet ports (maybe some establish sftp and some just ftp connection?). Some ISPs throttle your speed, they identify which packet it is, if it's "illegal" (i.e. bittorrent, etc.) it'll figure out which port it comes from, and throttle that port to almost zero.

MaximRecoil

14th February 2006, 20:49