Hello,

 

I have periodic stuttering video from the server to my apple TV and my macbook pro (so I know it's not the playback client)

 

At first I thought it was only video_ts folders that were spread over different hard disks, as I had added some dvd's to the server when the disks were getting pretty full (I've since added another disk and there's plenty of room now)...however, it's also happened to video_ts folders that are confined to just one hard drive.

 

It happens wirelessly, but also through the CAT6 cable, so I'm pretty much figuring it's somewhere in the unRAID but now sure how to fix it.

 

Will a cache drive help?  Right now I have a 2TB parity drive, plus 3 other 2TB drives.  Of those 3 other 2TB drives, 2 are pretty full and the other is pretty empty.

 

Thanks for the help.

No, the cache drive won't help as it is for writing files to unRAID and not cache for reading.

I'm by no means an expert but from what I've read, as a general rule, stuttering when streaming video is usually a network speed problem. I have no problems with standard def video_ts files from my UnRaid server and I know of others who are streaming full HD blu-ray rips from their UnRaid servers. I know wireless networks can cause problems but as you say you have the same problem over cat6 it's not that. However, I would stil look at your network hardware (NIC, switch, hub, router whatever) as being the likely cause of the problem.

You mentioned you are running Cat6. What are you devices 100mb or GigBit? What kind of content are you running? 480, 720, 1080.

Depends what you mean by stuttering .

 

As drives spin up you can have a delay in delivering data and if you are streaming already that can dependent on the software cause a stuter like effect.

 

However this would be periodic big hits and not common small stutters

As drives spin up you can have a delay in delivering data

 

Spin up will cause a delay only but by no means stuttering..

You mentioned you are running Cat6. What are you devices 100mb or GigBit? What kind of content are you running? 480, 720, 1080.

 

There is no video content over 50mbps. 100mbps is sufficient for all retail video.

While you "know it's not the playback client", it could be the playback client.  Or the codecs.

 

I don't do much playback on Macs but I've found Media Player Classic and the k-lite codec packs to be the most reliable combination for smooth playback in Windows.  Even with the codec pack installed, I've found Windows Media Player and VLC to occasionally have trouble with some videos.  Stuttering, audio out of sync, subtitles stuck on, etc. even when playing back from a local drive.  The MPC/k-lite combo has yet to fail me from a local source or network.

 

So do your videos play back properly when read from a local source?  If they do, the next question would be what your network equipment is and what's hooked up.  Then your sustained read/write speeds to/from the array.

 

FWIW, I played back a 25 gig 1080 video last night from my unraid setup without a single glitch.  Streamed beautifully, running a little under 3% network utilization on average.  Even a 100mbit network should be able to support that with bandwidth to spare.

You mentioned you are running Cat6. What are you devices 100mb or GigBit? What kind of content are you running? 480, 720, 1080.

 

There is no video content over 50mbps. 100mbps is sufficient for all retail video.

 

Very true, but I've seen people try and run video over 10mbs connections.

If you can connect the client straight to unRAID using a crossover network cable and see what happens. Use static IP address on the same subnet.

As drives spin up you can have a delay in delivering data

 

Spin up will cause a delay only but by no means stuttering..

 

Sure it can. I depends on what people define stuttering as. Ive seen people in XBMC support channel saying sturreing but mean a stutter (singular). Also some players are crap at dealing with file transitions and go mental causing the last few seconds of good data to stutter as it trys to get the next CD or the like.

 

Its the semantics of the wording vs the actual problem

As drives spin up you can have a delay in delivering data

 

Spin up will cause a delay only but by no means stuttering..

 

Sure it can. I depends on what people define stuttering as. Ive seen people in XBMC support channel saying sturreing but mean a stutter (singular). Also some players are crap at dealing with file transitions and go mental causing the last few seconds of good data to stutter as it trys to get the next CD or the like.

 

Its the semantics of the wording vs the actual problem

 

Multiple drives, and so multiple spin ups or downs, would also cause multiple stutters...

 

Certainly worth seeing if there is any spin up or down activity at the time of a stutter.

The combination of some players, with certain settings, using SMB rather than NFS or HTTP, can cause stuttering regardless of how good your network is. 

 

Somewhere in your player should be a setting for how much to buffer.... increase it.

 

Try changing to NFS rather than Samba

 

Try playing from a disk share rather than a user share.

FWIW,

 

I have zero stuttering watching 1080p videos through my PCH C-200 off my unRAID, and I have 9+1 2TB -EARS drives, via CAT5e cables, however, I don't have much success watching those same 1080p videos using software players on either my 2008 Mac Pro (dual 2.8, 12GB with nVidia GTX 285 card) or my 13" 2009 MacBook Pro 2.26.  Standard Def video's play fine.

 

I don't have an Apple TV.

 

For the computers, currently, all the available software players for OS X do NOT use hardware acceleration as far as I'm aware of.  VLC may soon come out with a hardware accelerated version.

Also for what it's worth, I too have no problems with stuttering when streaming uncompressed 1080p Blu Ray rips with HD Audio from my UnRaid server to my HDI Dune using SMB over a 10/100 cat 5 network and going through 2 switches.

For the computers, currently, all the available software players for OS X do NOT use hardware acceleration as far as I'm aware of.  VLC may soon come out with a hardware accelerated version.

Plex/nine and Plex/eight with a replacement binary can use hardware accelerated playback. With that, I've been able to play 1080p on my various Macs (same age as yours, one a bit older).

I have had problems with shuddering, This was after I discovered that my computer could not handle High Def.  I was watching the HIDEF version of Earth (with Richard Attenborro of course) and I could not get the video to play properly.  found out that my PC (and older 3Ghz Pentium) which is not a dual core was having issues (as well as the video card which is not the best)  The best I can figure out is my video card was just to slow to handle it, so I will replace it eventually.  The same video played on my laptop which is on the same network just a dual core Pentium.  I use Boxee for my playback and has worked good for me.

 

Sideband Samurai

For the computers, currently, all the available software players for OS X do NOT use hardware acceleration as far as I'm aware of.  VLC may soon come out with a hardware accelerated version.

Plex/nine and Plex/eight with a replacement binary can use hardware accelerated playback. With that, I've been able to play 1080p on my various Macs (same age as yours, one a bit older).

 

Tanks for the heads up!  Tho with the C-200, I don't see the need to use my Macs anymore as media players.  I first started out trying my MacBook with mini-DisplayPort to HDMI with Plex 0.8.5 to see if a Mac Mini would be able to handle the chores of an HTPC, but Plex kept crashing on me; sometimes taking the Mac down as well.  In addition, there is no way for HD Audio to be passed through in any Mac configuration (the Mac Mini HDMI version can't either), so that already was the deal-breaker that steered me to a non-Mac solution.  Enter the PopcornHour C-200 for me...

Stuttering can be dependent on many factors. Most the time its wireless that causes the problem. Next up I would check the firmware on the hard drives. I had many seagate 2tb that would stutter quite a bit and once I upgraded the firmware to the latest version fixed that problem. The next cause is the spinup delay time. To test just spinup all the disks.  After this its the media players fault. Apple tv  is not the best for playing HD material. I have an popcorn a110 and its hard sometimes, c200 best way to go for now. I am going to get the boxee box and play with that in November. BTW do you have 1st gen apple tv or the new one that only does 720p?

I've just found that my unRaid is stuttering and isn't playing iso files on one of my drives.  It is a Samsung.  I'm thinking of pulling out of the array and going with more of the Western Digital drives that are working flawlessly. 

 

Will I be able to pull the drive out and replace it with a new drive, format it and then let it move the data from parity?  I have a second backup so I could also delete what's on that drive, switch out the drive and then copy my backup media to it.

 

Suggestions?

I've just found that my unRaid is stuttering and isn't playing iso files on one of my drives.  It is a Samsung.  I'm thinking of pulling out of the array and going with more of the Western Digital drives that are working flawlessly. 

 

Will I be able to pull the drive out and replace it with a new drive, format it and then let it move the data from parity?  I have a second backup so I could also delete what's on that drive, switch out the drive and then copy my backup media to it.

 

Suggestions?

When replacing a drive with a new one you do not format it, you simply replace it and then press "Start" to let the array re-construct the data onto it.  It is not re-constructed from parity, but from parity and all the remaining data drives.

 

The odds of it being the drive is very slim.  It might just be that the movie on that drive has a higher bit-rate than the movie on the other drives.  Most drives can be read at a rate between 70 and 100 MB/s.  Movies are typically somewhere under 5 MB/s.

 

I've just found that my unRaid is stuttering and isn't playing iso files on one of my drives.  It is a Samsung.  I'm thinking of pulling out of the array and going with more of the Western Digital drives that are working flawlessly. 

 

Will I be able to pull the drive out and replace it with a new drive, format it and then let it move the data from parity?  I have a second backup so I could also delete what's on that drive, switch out the drive and then copy my backup media to it.

 

Suggestions?

 

You can also just pull the drive out and let unRaid reconstruct the data on-the-fly (ti will read all the other drives and provide the data via parity-reconstruct).  If the studdering is being caused by that one drive executing a bunch of read re-tries, that may confirm it.  Do a parity-check first before doing this though

I pulled the Samsung drive that is giving me problems and replaced it with a Western Digital.  It took most of the day to re-build.  I just tested it and WOW!  It's working beautifully, now.  No stuttering.  I thought I'd have to delete the files written over the weeks to that drive (400 Gigs) and rewrite them from my original files.  I figured the files were written to that drive corruptly.  Not the case.  I guess it got written correctly but had troubles reading the info back.  Therefore the rebuilt files are working!  

 

I'm back up and running and QUITE IMPRESSED!

 

I brought the Samsung drive to work and dropped it into an external drive dock.  No response.  This is actually my first drive to fail me.  I guess I have been lucky over the years.