Im at my wits end. I know this was a common problem but Ive searched and searched and just cant figure it out.
CPU: AMD Phenom II X6 1035t @ 3.145ghz (5644 Passmark Score)
Memory: 8GB DDR3
HDD:Mutliple Storage drives, OS on SSD
OS:Windows Server 2008 R2
Network: Gigabit Ethernet
Plex server: 1.3.3.3148
Router: Asus N66U with gigabit switch
I get stuttering when enabling subtitles, and only when enabling subtitles. I can force it to trans code a stream at 12Mbps/20Mbps whatever, and it is flawless. When I enable subtitels however I get intermittent stuttering or audio problems or crashes ect. This is with multiple different files, attempting to play back on multiple devices. CPU never goes above 50 percent. Plenty of RAM left. Hardwired over Ethernet. Disabled windows defender. Watching RESMON on the server during stuttering playback and I dont notice anything strange. How can I track down whats causing this issue? Thanks.
The question is not always the overall Passmarks of the processor. With subtitles, or any video processing, it is the per-thread throughput capability.
Subtitles, in your case, due to the player / client you’re using, obviously need to be burned-into the image. This is what mandates the transcoding and the demand for CPU resources. It’s still a largely single core process for each frame. yes, the others help with decoding, preparation, and subsequently output but only one can put thw subtitles onto the video frame.
Thanks for the response. I dont understand why I can trans code any video at all at any bitrate, but the same exact video causes stuttering playback if the subtitles are enabled. The exact CPU is A AMD Phenom II X6 1035t running at 3.145
This is currently what Im running.
This is a snapshop while playing a stuttering file
If you will grab the XML (get info -> view XML) and post here for what this info represents, I’ll ask one of the transcoder team guys to take a look just to make sure I’m not missing something obvious…
its not just one file. I have tried to play multiple files and they all seem to give me difficulty. They are all pretty much 20+ GB .mkv files. Here is the xml of one that always gives me trouble.
Yes, I have the problem with h264 as well, and again the problem only occurs with subtitles on. If it was a problem with VC-1 and my hardware, wouldnt it cause problems anytime I tried to transcode the file at all? i cant quite tell why but Ive got a feeling that its a storage issue. Could this be possible? Its like the old jm micron controller problems when SSDs were first coming out, and there was an occasional .5 second delay. It feels kinda like that, like everything is chugging along fine for a min then at random it just freezes for .5 a sec, and then continues. But again, only when subtitles are on.
Ive had the problem with every single movie Ive tried, but I just had a successful run with a TV episode. Subtitles on and no freezing. 175MB .mkv H264.
It’s possible it’s hardware. What seems more likely, (presume you’re on Win 7?) is a memory cleanup burp. You are tossing around a fair amount of data in sockets / pipes between everything going on plus the transcoder has its buffer (transcoder temp dir).
I don’t use SSDs but could you be experiencing a ‘multi-page wipe’ (trim) delay by the SSD itself? That’s inherent to a SSD and will slow down I/O while it does what it needs to.
Also a ‘windows-ism’… if the system tmp dir is loaded up with a lot junk (files) in it… while windows is doing other things (your playback) if it gets hung up on walking that directory list, it will burp… I can make that happen on demand.
I’m running Windows server 2008 r2. The transcoder temp file is on a standard mechanical drive. The SSD only has like 16 gigs free on it. I’ll try and mess around with it some more tomorrow. How can I check for this memory cleanup burp, or prevent it?
I’m running Windows server 2008 r2. The transcoder temp directory is on a standard mechanical drive not an SSD. The SSD only has like 12 gigs free. I haven’t done to much testing but it does seem to freeze more frequently on larger file sizes. I’ll try and actually test that. How can I check for or prevent this memory burp?
There’s nothing you can do with Windows memory cleanup. If you can reboot it, run the tests again, and behavior is different, you have your answer; Memory fragmentation. Such behavior has been a Windows signature since the adoptions of the NT v6 kernel.
Well thats unsatisfying. If it were a windows problem then everybody would be experiencing it and plex would be unusable. Obviously thats not the case. Is there anything I can check for in logs to try and narrow it down? Is windows 10 any better that older versions? After more testing I get error messages saying either your machine is not powerful enough to play back… or your connection is not fast enough to stream… They seem random though, and the same file with subtitles enabled can throw either error.
I’ve asked with the ninjas as well. I get one seemingly common answer. It’s not an answer imho but I’m a Linux guy. “it’s server 2008, anything’s possible”. I will continue to see what I can figure out / learn from others (staff & the transcoder team).
Some other points which did come up. Jumbo Frames? I forgot to ask you. Those will cause stutters seemingly at random on the best of networks. Jumbo frames have to be perfect. Another is the switch/router itself. If everything is running through the modem/router and there is latency at the wrong moment, stutter. If it’s all machine-local (via the loopback) that’s unlikely. What is the playback client?
The playback client is not the machine with data stored on it, but streaming to another device. All devices stutter including Android clients, hard wired Chromecast, and other Windows PCs. I tried running the server in safe mode and it did not help. I will look into jumbo frames as I’m pretty sure they are enabled. Network equipment consists of a Asus N66U running the latest version of asuswrt merlin. A Netgear 16port gigabit switch powers everything else.
The rule of thumb for Jumbo frame: Unless you have a specific need for them and know exactly what you’re doing, turn them off. They will spoil the soup every time.
Ok jumbo frames were enabled on the Server, but not on the router. I disabled them but I still get the stuttering on an android client. After multiple test runs I got both the your connection is not fast enough and your server is not powerful enough errors.
During a test run I get a 2 second solid freeze then it continues as if nothing happened at 52s, 2:04, 2.28, 4.42 after playback started.
@PoppinJ said:
Ok jumbo frames were enabled on the Server, but not on the router. I disabled them but I still get the stuttering on an android client. After multiple test runs I got both the your connection is not fast enough and your server is not powerful enough errors.
During a test run I get a 2 second solid freeze then it continues as if nothing happened at 52s, 2:04, 2.28, 4.42 after playback started.
Do you have the log files for that ? If the server hasn’t been used since you did that Settings - server - help - download logs will get all the log files.
If you can attach them here, I’ll go through them and compare with my log files.
