TMT5 & Playing from whs2011

[ikon 439]

I have a very nearly identical setup. I was also having stuttering problems in TMT5 despite 50+MB network speed.

 

Turns out on my Win7x64 HTPC there is a default network throttle in the registry (read here http://support.microsoft.com/kb/948066) -

 

I tweaked my registry to 70 and - no problems since. I can stream easily, no stuttering, smooth playback.

 

Hope it works.

What about other network activity. Have you tested network performance for other apps while TMT5 is playing something?

[thepregnantgod 0]

That's a good question, but no, I have not tested it. The network throttle really only affects my HTPC when I'm streaming a Bluray. I've not had to use the network and watch a bluray on my 42" at the same time - usually just shoveling popcorn in and drinking a beer! When using the HTPC for other things - surfing, updating, etc. I've seen no affect. Additionally, changing the network throttle allowed me to push files (transfer over) at faster rates - while the kids are watching television (I can do maintenance while they're using the HTPC without them coming up stairs saying, "Daddy, something's wrong with the tv!"

[ikon 439]

That's pretty cool. Just to be clear, are you saying that the change not only makes streaming smoother but also gives you faster file transfers while the streaming is going on?

[thepregnantgod 0]

Yes. The article states, "Because multimedia programs require more resources, the Windows networking stack implements a throttling mechanism to restrict the processing of non-multimedia network traffic to 10 packets per millisecond.

 

The throttling will come into effect only when you are running multimedia programs that are time sensitive. However, this throttling mechanism can potentially cause a decrease in network performance during the active multimedia playback period. This decrease in performance is likely to occur only on high speed networks that are saturated to maximum capacity."

 

Thus, when WMC7 is running (the kids watching cartoons or in the instance that I'm streaming a Bluray), the throttle kicks in. In other words, Win7 sees a multimedia application running and reserves resources/bandwidth for it. Problem for me (and I think the OP) is that it doesn't recognize the streaming of the Bluray through a Virtual Mount as part of the multimedia application - thus it is throttled. Or...in the instance that I want to move around some files on the HTPC but the kids are watching cartoons my transfer speed was very low. Once I edited this registry to 70 - I was able to get 40-50mbs throughput.

 

To be clear, transfer speeds only seem to be throttled when a "multimedia" application is running on the HTPC. When I mount my Bluray via CloneDrive (slysoft) and play it via TMT5 a few things happen. First, TMT5 is a multimedia app so throttling starts...however the Clonedrive appears to be a simple file transfer (as if I were copying a file from the WHS to the HTPC) - thus throttled. I would get stuttering and only get at most 10mbs in TMT info window. Once I edited the registry as noted in the MS article, I could get full transfer via Clonedrive and TMT5 didn't stutter.

Edited October 19, 2011 by thepregnantgod

[ikon 439]

ah. So you believe the virtualization is the issue. Interesting.

[pcdoc 114]

Interesting analysis but I do not quite agree with your theory on CloneDrive. Clonedrive is basically only to fake the system into believing that there is physical disk in the system and should have no impact to network performance

As I prefer folder structures to ISO I cannot prove my theory but I can tell you that when playing a BD stream on my HTPC using TMT 5, I am not throttled on the balance of my network. My typical speeds are 100-110 and 70-80 when play a BD disk. If you want to test our your theory, try ripping in folder structure instead of an ISO and see what happens. Interesting research non the less and thanks for bringing it to the forums.

[thepregnantgod 0]

pcdoc, you could be correct. There are a lot of variables in play; and, as I'm currently messing with my first WHS, I don't have the time to narrow them all down. What I do know for sure, is that by simply changing that registry I no longer saw any stutter. I'd like to know if the OP had any luck wit it.

 

Note, though, you are also correct in that Clonedrive is there to fool the system into thinking there's a drive there. But, regardless, the system also sees a lot of network traffic when the .iso is pulled from a network share. That, at the same time as running a multimedia application triggers the throttle. I have tested that - I've copied a bluray .iso over to the HTPC - kept it local. Mounted it via Clonedrive and then played it via TMT5 (all this prior to the registry hack) - no problem at all! So, what I can narrow down is that my problem only occurred when transferring the .iso via the network and trying to play it simultaneously. I suppose I could test a simple file copy while watching television and see if the rates differ when not watching television.

 

More to follow.

Edited October 21, 2011 by thepregnantgod

[pcdoc 114]

Look forward to learning about the conclusion. I am certain there is allot of data pulled via the network when running the ISO but I am wondering if it is any worse than a standard BD stream from a folder. From what I have seen, BD playback from a folder hovers between 14-20 Megs a second per stream. Good luck and keep us posted.