MVP beta update

[dagar]

I telneted into the MVP and checked the eth0 statistics and saw some errors as well ... low count though ... will look more over w/e

[rickw]

Originally Posted by dagar

I telneted into the MVP and checked the eth0 statistics and saw some errors as well ... low count though ... will look more over w/e

I figured out how to telnet to the mvp...but what's the command to get the eth0 stats?

[Stuntman]

Originally Posted by rickw

I figured out how to telnet to the mvp...but what's the command to get the eth0 stats?

I used 'ifconfig'

When I look I do see RX Overrun errors as well... this could very well be part of the problem.. anybody else seeing this that has been able to telnet into the MVP??

[MrApollinax]

I'm seeing overrun errors as well. I'd try to use netstat but it seems that it isn't part of this distro.

[marneb17]

Originally Posted by Stuntman

anybody else seeing this that has been able to telnet into the MVP??

Yes

[MrApollinax]

okay, when playing a video file eth0 takes continuous RX overrun errors. Comparing that to my ethereal captures I can see that all the errored frames are one way, from the server to the MVP. The captures show all the packets from the MVP to the server are fine.

[Stuntman]

Originally Posted by MrApollinax

okay, when playing a video file eth0 takes continuous RX overrun errors. Comparing that to my ethereal captures I can see that all the errored frames are one way, from the server to the MVP. The captures show all the packets from the MVP to the server are fine.

I am a linux hack at best.. but would this error imply that there may be an issue with the driver Sage is using on Eth0 for the MVP? Perhaps the receive buffers are too small? Most of what I've seen on Google searches seem to blame the NIC's driver.. which is, perhaps, why it is an incoming, or RX issue for us only..

Thoughts?

[MrApollinax]

I think the best way to explain it is to picture your NIC card as a bucket. That bucket has a large hole on the side that lets traffic flow out in a manner that can be handled by your system. The bucket fills up and traffic stops momemtarily and traffic flows out quickly so traffic is never "lost" and the bucket can fill up again. Overrun happens when too much traffic hits your NIC and the bucket literaly overruns and you loose packets.

Once a packet is sent the sending device expects a message from the other end that it was recieved. If it doesn't get one the sender re-sends the packet. Get enough of these resends and your network performance takes a pretty big hit. For something like VOIP or streaming video this can result in static in your voice calls, video rendering problems etc.

Right now this is a shot inthe dark since all i can really troubleshoot on my end is the network side of it. But from my experience with Video on Demand and VOIP the symptoms the MVP has right now look like traffic handling issues. Other devices on the network operate fine and other TCP heavy apps like VNC do not exhibt the stuttering.

[Stuntman]

Can anybody verify if the original software that runs on the MVP also has this overrun issue, or if perhaps it is something that exists only in the Sage modification??

[MrApollinax]

I probably wont be able to try this until later this weekend but the easiest way to handle this is install the hauppauge software and disable the SageTV services. If you can telnet into the MVP with the hauppauge image try streaming an mpeg file and run "ifconfig eth0" from your telnet screen. It'll be pretty easy to see if the problem still exists or not.

[_Demo_]

The buffer in the mvp ethernet chip is small, that's why you can see those overruns. It shouldn't cause problems.

_Demo_

[MrApollinax]

Thanks for the info _Demo_ I'll stop chasing down that particular trail then.

[Stuntman]

Originally Posted by MrApollinax

Thanks for the info _Demo_ I'll stop chasing down that particular trail then.

I'm still curious, for anybody who has the orginal Hauppauge software installed too.. to see if it also gets these errors.. obviously they shouldn't be there, but they may be rather insignificant in the grand scheme of things.. But I see LOTS of them when I stream, and it becomes a bigger problem over wireless, which doesn't have the 100mb connection to speed up all the retries.. something that might be an issue when the wireless MVP comes out..

Is there any way to increase the size of the buffer onboard?

Anyhow, will be glad to see it resolved.. whatever the cause may be.

[MrApollinax]

I'd definately try it vs the hauppauge software. It'll at least give us a good bseline control to test against.

[MrApollinax]

FWIW my Xbox running XBMC does not stutter at all when playing my videos. I'll try switching over to the hauppauge software this weekend and see how that works out.

[MrApollinax]

Last update for the weekend. I've switch over to the Hauppauge software and there is no stuttering at all. Also hauppauge seems to have disable the telnet deamon in their version of the MVP image so i cannot verify the buffer overrun. My etherreal capture show that this implementation also has TCP checksum errors however now I get straight ACKs in the stream rather than SYN,ACKs. Right now the Hauppauge software works but the SageTV interface does not. I'll stick with the Hauppauge software for now and see if it get any worse over the weekend.

[tipstir]

Well this is my first post here and I've been supporting the Media MVP over at GBPVR side since 11/2004 thru 01/14/2006 creating skins, tools an etc. Time to move on since I've heard SageTV software now supports MVP!

How does one get on the beta team an etc?

[Opus4]

If you mean in order to use Studio, you don't have to be in any beta group; it is included for everyone in v4 now. You can even open a Studio instance on your server via the MVP by using the Customize command from the MVP UI.

- Andy

[Stuntman]

Originally Posted by MrApollinax

Last update for the weekend. I've switch over to the Hauppauge software and there is no stuttering at all. Also hauppauge seems to have disable the telnet deamon in their version of the MVP image so i cannot verify the buffer overrun. My etherreal capture show that this implementation also has TCP checksum errors however now I get straight ACKs in the stream rather than SYN,ACKs. Right now the Hauppauge software works but the SageTV interface does not. I'll stick with the Hauppauge software for now and see if it get any worse over the weekend.

That is actually quite good news.. it, along with the fact that other devices can stream the same video without stuttering seems to indicate that it may be something in the code within the MVP that is causing so much grief.. I know I'm not the only one who has been tweaking NIC's, Routers, Switches, drivers and everything else in an attempt to identify something other than the MVP..

Hopefully this, and other tests in and around this area will lead to some progress!

Baby steps!

[MrApollinax]

okay, over the weekend I ran the Hauppauge software without too many problems. Some of my audio went out of sync but a quick reset fixed that somehow. Anyway I'm trying to remember if I had this problem with the alpha mvp.bin that solved the problem with the DGL-4300 router. I'm running with the newest mvp.bin with the on/off remote capability. I'll try to roll back to the alpha tonight and report back my results.