More on Vista network performance issue

More on Vista network performance issue

Summary: I'm still trying to get a handle on this Vista network performance issue, especially what causes it and what the effect is.


This is part 3 - Part 1 | Part 2

I'm still trying to get a handle on this Vista network performance issue, especially what causes it and what the effect is.

Here's what we know so far:

  • Playing an audio (and it seems a video file, even if it has no audio) seems to cause a dramatic drop in network performance between two machines running 1Gbps Ethernet adaptors.
  • The cap seems artificial given the shape of the charts being produced (this is a guess, but given how reliably I can reproduce it, I'm willing to go with it for now).
  • The problem isn't isolated to a single media player.
  • The performance drop is seen even if the media being played is paused, but with no media loaded into the player, performance is normal.
  • Starting to play an audio/video file mid file transfer causes an almost immediate drop in network performance.
  • Recording a sound file using Sound Recorder causes the same performance drop.
  • Closing down the media player seems to cause network transfer to flatline to (or close to) zero for several seconds before resuming at full speed.
  • Application of the Vista performance and stability updates (KB938194 and KB938979) does not fix the issue.
  • I can reproduce this effect on different systems, thus ruling out a single PC issue.
  • This issue does not seem to be present on XP.
  • I don't believe that this issue is being caused by CPU or drive stress - during media playback I'm not seeing any stress on the system and I can't reproduce the network performance drop by stressing the CPU or drives otherwise.
  • I've passed this information on to Microsoft, but so far I've received no comment.

Let me now field some questions from readers:

  • Are all versions of Vista affected? I can see the effect on Home Premium, Ultimate and Business.  I've not tried any other versions yet.
  • What about other versions of Windows? I've only tried XP and that OS doesn't seem to be affected.
  • Do you see any odd processes float to the top of the Task Manager list when network performance is being throttled? I've looked and I can't seen anything odd.
  • Is this related to DRM? No idea.  DRM in Windows Vista is very much a closed black box.  Since the issue seems to relate to audio and video playback and recording, it's possible.
  • Is this a QoS (Quality of Service) issue? Maybe, but I can't see how this kind of throttling of network performance by design.  A 50% drop in performance is a huge (and for some, completely unacceptable) drop in performance.
  • I see you've tried Windows Media Player.  What about iTunes/Real Player/etc (insert media playing software here)? I've tried a few different media players and all seem to cause the drop in performance.
  • Is it audio, video or both? Seems to be both.
  • Does a packet sniffer show up anything odd? I've only had time to look casually, but I can't see anything out of the ordinary.
  • Is the effect noticeable at network speeds less than 1Gbps? Yes, although it's not as noticeable.  On gigabit LANs I'm seeing an almost consistent 50% reduction.  Transferring files over a 100Mbps LAN seems to cause a reduction closer to 25%.  I'd want to do more study before being 100% confident of these figures. Image below is of a transfer from a system with a 100Mbps Ethernet adaptor to one with a 1Gbps Ethernet adaptor. Network performance drops on slower LANs
  • Do normal run-of-the-mill Windows theme sounds affect network transfer speeds? Yes, they seem to.
  • How does this affect Media Center and media extenders? No idea.  If you're in a position to try this, I'd appreciate if you could let me know what the effect is.
  • Do you have a workaround? No.
  • Any comment from Microsoft? Not yet.  If/when they comment, I'll be sure to post the information I get.

I'll keep you posted.

Topics: Hardware, Microsoft, Networking, Windows

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  • Shssh. Don't let George or Ed hear this problem.

    They suffer from Stockholm syndrome and so will always side with their captors that hold them hostage (Microsoft). It must be a hardware issue, driver issue, user error or the phase of the moon; anything but MS is to blame for this.

    I am postive this has everything to do with DRM management. Although I am sure George will tell me otherwise...
    • It's a configuration issue...

      This is entirely Adrian's fault. When Vista is installed he didn't manually copy the 'WorkingNetwork.dll' from the install disk to a temporary directory (hidden) on the C: drive. If he had done that he would have gotten the prompt during installation that allows him to choose whether or not he wants a full copy of his genome sent to the RIAA every time Windows goes 'ding'.

      Every time someone whines about Vista like this, somewhere a kitten gets eaten by a big green pillow looking thing. When will people learn?
      • That's just silly and WRONG

        Everybody with the least bit of computer knowledge knows that WorkingNetwork.dll will be properly installed and set if you just hold down the
        G-X-9-Tab-I-/-;-[-F2 keys for the entire installation.

        Oh, by the way, just get a puppy. They only get eaten after 12 whines.
      • Like the name George_Bott...

        makes me want to change to ed_ou
        • what about "Ou_No" ?

          • Doesnt follow the pattern...

            but it is good.

            Ed Bott Ed_ou
            George Ou George_Bott
          • how about Ou_Carroll?? i think its a song too

          • How about an educational aspect

            How about Adrian_Ed_Ou. It would be pronounced ;-)
      • 9.0

        You did a good job of parodying both George and Ed (for your next challenge, mix the two). Thanks for the laugh.
        John L. Ries
    • George will tell you in a couple of days...

      how apple pulled this off :)
      • Is that George's definition of couple or the rest of the worlds? (nt)

        • If it's George's . . .

          We might NEVER know the answer!!! ;)
    • I have asked Ed directly

      And in Adrian's talk backs if either George or Ed have reproduced the problem. Giving them the benefit of the doubt, maybe they are actively troubleshooting the problem. It is suspicious however, given their tendency to jump all over Adrian from time to time, the continuing silence is getting deafening. They still get the benefit of the doubt for now though.

      In any case, it is a PEBKAC problem, music has no place on a networked computer. :D

      • Maybe they are working on their apology to ...

        Peter Gutmann, oh wait this is George and Ed, that aint gonna happen, maybe they are looking for a new story to bash Apple, so they deflect attention from this issue.
      • Hahahah

        "In any case, it is a PEBKAC problem, music has no place on a networked computer."

        Adrian Kingsley-Hughes
    • Are you just stupid?

      Ed's pointed out a number of problems with Vista. He is just sick to death of idiots like you stating 'it has to be DRM management' without the slightest evidence or clue as to what they are talking about.

      Your just a whiner. You'll note Adrian at least went through some steps to figure out what was happening, and clearly seperated what he knows about the problem from what he is guessing.

      I would suggest you take a lesson from that.
      • Good point, however...

        It may not be DRM related, but it might. The lack of input from Ed and George, given the number of times they have been all over Adrian for various Vista blogs, their complete lack of input, or addressing these in their own blogs does raise an eyebrow or two.

        • Then again...

          it might be one of several dozen other issues. Take a number; get in line.....
          Jeremy W
      • No sense of humour

        My Vista works fines on my system thank you. I have never whined about Vista. Ultimately though I don't see why people complaints should be considered whining. Looks like someone else has Stockholm syndrome...
        • I have a sense of humor. Kind of...

          But I'm with Ed on this one; complaining and whining are very different things. Complaints involve details or examples, some which can be reproduced. Most of the Vista bashing around here contain neither, just 'heart felt' stories about how Bill Gates kills kittens every time you boot.

          I would like to reiterate that Adrian should be commended; details, analysis, and supposition, worked out, thought out, and separated clearly.