Studdering in new beta!!

[mikejaner]

I upgraded to the latest HD Extender firmware and 6.4.6 yesterday, and ever since, I have been getting this really really really annoying studdering during playback of live tv or a recorded show. It's more like half second pauses which happen randomly but up to a few times during a five second interval. Is anybody else seeing this?
I am exclusively using HDPVR's right now, and watching with HD Extenders. WAF is really low right now.

[srothwell]

Originally Posted by mikejaner

I upgraded to the latest HD Extender firmware and 6.4.6 yesterday, and ever since, I have been getting this really really really annoying studdering during playback of live tv or a recorded show. It's more like half second pauses which happen randomly but up to a few times during a five second interval. Is anybody else seeing this?
I am exclusively using HDPVR's right now, and watching with HD Extenders. WAF is really low right now.

only thing I've noticed is on Placeshifter that if I'm watching Live TV, I need to go back about 10 seconds to make a smooth picture otherwise I will also get hesitations.

This seems to happen eery few beta cycles.

[mikejaner]

I am trying some debugging, but it looks like the network light on the HD Extender is not constantly flashing when a video is playing, and when it is not on is when the video pauses. It seems to me like it's not buffering right or SageTV is not sending a constant stream to it.

Here's a clip from Telnet to the Extender:

stc 23089 a pts 1038989 (23088)
v dec pts 1039938 disp pts 1038437
audio pts is smaller than stc, entering paused mode
demux 0.00 video 5.87 audio 1.53 spu 0.00
stc 23117 a pts 1040303 (23117)
v dec pts 1044443 disp pts 1039938
demux 0.00 video 9.39 audio 1.92 spu 0.00
stc 23800 a pts 1071038 (23800)
v dec pts 1074473 disp pts 1071470
audio pts is smaller than stc, entering paused mode
demux 0.35 video 28.42 audio 6.07 spu 0.00
stc 23833 a pts 1072514 (23833)

UPDATE:
Bug Submitted

These "entering paused mode" lines from the telnet session definately go with the studdering.

[bwallis]

I just upgraded this AM to the newest version and my HD-PVR files stutter horribly. Not just the ones streaming live, but also the ones that were already recorded. I checked the codecs running and nothing else has changed.

Interestingly, I upgraded the server and one client which both have problems. The bedroom is still running an older version 6.4.5 and everything works fine.

I am downgrading the den client for now to see if this helps. Let me know if anyone finds anything out.

Brent

[Motofreak75]

the stx is running out of buffer " video 5.87" means 5.87% left.

What type of file are you playing and what device was it recorded from ? because the only I see this is playing AVC with either Ac3 or DTS and the video bitrate goes really high (above 40mbit)

and my server can max out 1gigbit connection at 120MB's (bytes not bits) but I still get a buffer issues with all my stx's

[mikejaner]

I am recording from my cable boxes, so 1080i at the most, and stereo input, so nothing out of the ordinary. Also, video playback was pretty much smooth before the firmware update, and version update on Thursday/Friday. Nothing else in my system changed.

[mikejaner]

Update:
I made some changes to see if I could narrow this down, with positive results.
I have Gigabit switches in my network, and have been using them for a while. I took my SageTV server off of the gigabit switch and put it with the HD extenders on a 100 Megabit switch, and the studdering went away. What would have changed?
I noted this in the bug report, but from a visual standpoint, the network light on the HD extender would blink intermittantly while the SageTV server was on the Gigabit network. Sometimes it would stop blinking for as much as a half second or so. That is right when you would see the paus in video.
After I put the server on the 100 Megabit network, the network light on the HD Extender blinks almost constantly, which is good in my book.
This tells me something changed in how SageTV sends data to the extender which affects gigabit network switches, because the network card on the computer is 100 Megabit. Yes, I know it doesn't matter to the SageTV server speedwise, but my point is what would affect a gigabit switch that would kill the packets, vs what SageTV was doing before?

Oh yeah, and see my post from June, where I was troubleshooting the extenders, and ended taking them off of Gigabit switches also.
http://forums.sagetv.com/forums/showthread.php?t=33627

So basically, I had my extenders and computer on Gigabit switches all the way up to the beginning of my HDPVR experience, so May/June, and then it all went downhill for me. Maybe it's something in the 6.4 code altogether. I was streaming fine with the HD extenders since December with HDHR's which use more bandwith up until then.

[reggie14]

Have you ever used Wireshark? You could try capturing packets on your server. It might be interesting to find out what frame size is being used, and the amount of time between frames.

[Slipshod]

Originally Posted by reggie14

Have you ever used Wireshark? You could try capturing packets on your server. It might be interesting to find out what frame size is being used, and the amount of time between frames.

If you do, let me know - I'd be interested in reading it. Sounds like it could be a TCP performance problem to me, and I've got a little bit of experience diagnosing those.

[mikejaner]

Originally Posted by Slipshod

If you do, let me know - I'd be interested in reading it. Sounds like it could be a TCP performance problem to me, and I've got a little bit of experience diagnosing those.

That would be great. I had thought about running a Wireshark capture at the time. My greatest priority was getting my wife back to the state of liking me again, hence why I probably seemed a little panicked at the beginning.
I will run one tonight after I get home from work, and try to post, or link to it once it's done. It's gonna be big, but we'll see how small I can get it.

[gplasky]

Originally Posted by mikejaner

I upgraded to the latest HD Extender firmware and 6.4.6 yesterday, and ever since, I have been getting this really really really annoying studdering during playback of live tv or a recorded show. It's more like half second pauses which happen randomly but up to a few times during a five second interval. Is anybody else seeing this?
I am exclusively using HDPVR's right now, and watching with HD Extenders. WAF is really low right now.

These are the same symptoms that I am seeing. But I also saw it in the previous 6.4.5 beta. It onkly occurs with HD-PVR recordings. I also have HDHR recording that do not exhibit this. I will narrow my debugging to the network connection.


Gerry

[tmiranda]

I'm still on 6.4.3 and am seeing this too. I just noticed it last night watching pre-season football @ 1080i from my HDHR.

[mikejaner]

I noticed it on 6.4.5, but it was like once every few minutes. It was under my threshold of pain, and I thought it might get cleared up as the beta cycle progressed.....then I installed 6.4.6 and all heck broke loose in my household.

[mikejaner]

Ok,
I have the to packet captures for you guys. Both are from the same exact video file from an HDPVR recording . One, (Gigswitch) is the one where my server is plugged into the Gig switch. The other (100switch) is the one where my server is plugged into the 100 Megabit switch. As predicted, it misbehaved on the gig, and ran perfectly on the 100Meg.
Here's the links to the files:

https://my.syncplicity.com/share/q2b...GigSwitch.pcap

https://my.syncplicity.com/share/lmc...100Switch.pcap

Have fun, and thanks for any help/feed back you guys can give.

[reggie14]

Originally Posted by mikejaner

Ok,
I have the to packet captures for you guys. Both are from the same exact video file from an HDPVR recording . One, (Gigswitch) is the one where my server is plugged into the Gig switch. The other (100switch) is the one where my server is plugged into the 100 Megabit switch. As predicted, it misbehaved on the gig, and ran perfectly on the 100Meg.

Well, the initial thing that I see in the gigabit capture is a lot of dropped/non-acknowledged packets. Certainly more than I would expect, by I'm an amateur at this. The 100mbit capture doesn't have any dropped packets, so I think there's a pretty good chance that the dropped packets is responsible for the stuttering.

So far I haven't found anything that would explain the dropped packets. Ordinarily I would say there's a good chance its a network hardware problem, possibly on the switch or even on the server. But, since multiple people seem to be experiencing this problem that seems a little unlikely. It's still something you should investigate if you have the spare network equipment (e.g. a extra gigabit switch).

In each case the server is pretty consistently sending 1500 byte frames. It doesn't seem like the HD100 should even be able to tell the difference between the 100mbit and gigabit cases.

[mikejaner]

Cool, thanks for the info. I might have access to a friend's Gig switch in the near future. What perplexes me is that these are new Linksys switches(last 6 months), and it has been quite happy until the last update of firmware and software. Also as a note, if I run jperf, and transfer files between servers, I get pretty much full 100 meg speeds.

[reggie14]

Originally Posted by mikejaner

Cool, thanks for the info. I might have access to a friend's Gig switch in the near future. What perplexes me is that these are new Linksys switches(last 6 months), and it has been quite happy until the last update of firmware and software. Also as a note, if I run jperf, and transfer files between servers, I get pretty much full 100 meg speeds.

I'm not sure what I think of the quality of Linksys equipment these days, but I agree that this is probably unlikely to be an equipment problem.

Also, while there seems to be a lot of dropped packets from the capture, it still looks like a pretty insignificant amount. You certainly wouldn't notice it during a file transfer. I'm actually quite surprised it's noticeable with playback on the HD100. It seems like the buffer on the HD100 should be able to deal with the occasional dropped packet.

It would be interesting to know if you see any dropped packets when you just do a file transfer from one machine to another. It's pretty easy to identify them in Wireshark. Wireshark will highlight the line in black, and you'll see a phrase like "TCP Fast Retransmission". As it implies, that indicates the computer transmitting information is resending a packet because the other side apparently never got it originally.

[mikejaner]

Good idea reggie14, I might try a packet capture during a file transfer in both senarios to see if it looks similar.

[Watch22]

I have my HD-100 hooked up to a NetGear 108T Gig switch along with 6 other machines. The switch is uplinked to a WatchGuard x10e firewall. I was having pausing HD content before the latest 6.4.6 Sage update HD-100 firmware.

Since the upgrade I have no shuttering or pausing on HD content. I watched "CARS" BluRay and and "Fantastic 4" BluRay without any dropouts or shuttering.

I would check the NIC in your media server, I have seen some off brands not performing well.

[jasongrimme]

As I understand it, this is an HD-PVR issue that needs a firmware update to resolve.

http://forums.sagetv.com/forums/show...4&postcount=14

In the meantime, if you can set your STB to output 1080i, you should have better performance.