Plex buffering issue & potentially excessive RAM usage.

[TremorAcePV]

Hi guys,

Firstly, system specs:
Two 4-core Xeons (E5450's) CPUs
32GB of DDR2 667MHz ECC Fully Buffered RAM
One 4TB Seagate HDD
One 40GB SSD & One 60GB SSD
CAT 6A ethernet between me and the server with Gigabit ports all along the way (no 10/100 ports).

So I upgraded from FreeNAS 9.2.1.5 to 9.2.1.7, and then upgraded Plex from 0.9.9.7 to 0.9.9.13.

Before doing this, I could stream multiple 1080p videos just fine and my RAM sat at around 19-23GB depending on what was going on.

After doing this, I can't stream a single HD video (720p+) because it will work for about 10-15 seconds then buffer. Then I wait for a minute or so to watch another 10-15 seconds and repeat. Music & Photos work fine.

My RAM sits at 25GB used whether streaming or not, and I haven't added content at all between upgrades. I have about 1TB of media and 1TB of backups on this server on a single 4TB HDD. The 40GB SSD is used for the jails themselves to live on while the 60GB SSD has yet to be put to work on anything specific.

When transferring things to this server, I get 80-90 MB/s transfer speeds, so I don't believe it's a bottleneck with the storage. The reporting on the GUI shows little HDD activity and around 30-40% CPU loads when streaming.

My idea (although I know little about the internal workings of FreeNAS) is that the RAM is running out although I have 7GB left. Something I read about FreeNAS using 80% at max and leaving the rest for other things which could be irrelevant here, but I'm not sure. 0.8*32 = 25.6GB which is right where it's at.

Any help is appreciated. Deduplication is not on.

 

[cyberjock]

What motherboard are you using?

Is this problem with streaming through Plex or via CIFS share? If it's through Plex what happens if you try to watch it through a CIFS share and use something like VLC on your desktop?

Is a scrub in progress?

 

[TremorAcePV]

What motherboard are you using?

Is this problem with streaming through Plex or via CIFS share? If it's through Plex what happens if you try to watch it through a CIFS share and use something like VLC on your desktop?

Is a scrub in progress?

Super Micro Computer X7DWN+ LGA 771

Plex it seems. If I play it through CIFS it works 100% fine. I can skip around and it instantly renders. I came and asked here because I figured it wasn't Plex since I can play the videos fine on a PS3 & Phone, but not through the web interface and the RAM usage stuff came up.

No. They are scheduled for Sundays. From the GUI and console, there isn't one running atm.

 

[cyberjock]

Yeah.. no doubt your 771 CPUs can't handle the workload. See this post I made just a few hours ago about some older tech...
http://forums.freenas.org/index.php...-6-disks-mirrors-vs-raidz2.23312/#post-141304

You'll find he had some performance bottlenecks just doing RAIDZ2 because of the parity calculations on socket 771 hardware. Literally 771 died in 2008 when Nehalem CPUs were released without a FSB. That makes it 6 years old though so I'm not sure if I should be surprised that you can't do amazing things with it.

Honestly, I see nothing at all about your RAM usage that I'd consider even remotely "abnormal". RAM that's not being used is money you spent on resources you aren't using.

We don't recommend 771 stuff, not even as cheap used stuff on ebay that is a "use it for now" type of thing. It's old. It's slow. It's a power hog. And the people selling it are selling it for cheap because it's not worth anything to people that know better. ;)

The CPUs themselves benchmark pretty well for today's CPUs and should be fine. Except FSB is a major buzzkill. Then you make things even worse for your FSB by throwing two CPUs on it. :(

 

[Ericloewe]

Yeah.. no doubt your 771 CPUs can't handle the workload. See this post I made just a few hours ago about some older tech...
http://forums.freenas.org/index.php...-6-disks-mirrors-vs-raidz2.23312/#post-141304

You'll find he had some performance bottlenecks just doing RAIDZ2 because of the parity calculations on socket 771 hardware. Literally 771 died in 2008 when Nehalem CPUs were released without a FSB. That makes it 6 years old though so I'm not sure if I should be surprised that you can't do amazing things with it.

Honestly, I see nothing at all about your RAM usage that I'd consider even remotely "abnormal". RAM that's not being used is money you spent on resources you aren't using.

We don't recommend 771 stuff, not even as cheap used stuff on ebay that is a "use it for now" type of thing. It's old. It's slow. It's a power hog. And the people selling it are selling it for cheap because it's not worth anything to people that know better. ;)

The CPUs themselves benchmark pretty well for today's CPUs and should be fine. Except FSB is a major buzzkill. Then you make things even worse for your FSB by throwing two CPUs on it. :(

Four CPUs, if they're quad cores, since Intel had no native quad cores until Nehalem. They just glued two dual cores together with the FSB.

If one of them needs something from another's cache, it'll have to go through the FSB, just like everything else (including RAM accesses!). This pretty much bottlenecks the CPUs in memory-intensive applications.

 

[TremorAcePV]

-snip-

Which, I would say, "Alright cool, I'll buy new hardware." if I hadn't been using this same server for the past several months with Plex, streaming multiple HD streams and everything being hunky dory. Unless something died, but nothing is saying there's a problem. HDDs are fine. RAM is showing up fine. Nothing is saying it's corrupt. CPUs are all appearing with their load % being normal, etc etc.

I'm not saying you are wrong in that the hardware sucks. I'm saying I don't understand why it would just suddenly change so drastically when I update FreeNAS for that specific reason. But I guess my understanding of it doesn't change why it is.

Thanks for the help though. You or resident Grinch mentioned to me before how this hardware wasn't a good idea, but I already own it, so may as well use it until I can buy something else. I stand by the fact that this is the cheapest way to get a large amount of ECC RAM, even if it means sacrificing potential power.

Also, I live in Texas. Power is cheap here. According to my watt meter, that server uses around 220w on average, which is about $25 a month in electricity here.

Oh well. Time to start saving up for the real NAS I always wanted.

 

[cyberjock]

I know there's been some pretty serious code changes in Plex in the last few releases. A friend that virtualizes his Plex server just 3 days ago had to go from 2 cores to 4 cores in the VM. He's been running 2 cores for more than 2 years without a care in the world and he could no longer stream stuff and had the same symptoms you had. Of course I couldn't rely on CPU% quite the same since it was a VM, but I knew from other indicators it was a lack of CPU resources.

I myself run Plex in a linux VM and I've got on my "to-do" list to move it to my FreeNAS box because I do have a desire to have more power for Plex. But ESXi's CPU resource allocation is a bit rough and giving the VM more cores isn't good for my ESXi server long-term so the better option is to move it to my FreeNAS box where I can have *plenty* of CPU power since my server is virtually idle 24x7 and the CPU is definitely overpowered (E3-1230v2). I've also deliberately not updated because I don't need to deal with the resource needs. I'm almost convinced that Plex has some kind of bug causing it to need so much more than before, but I don't know that for 100%.

To be honest, if you could hold out until next January you'll see DDR4 based systems become more price-conscious and that might be a good jump. DDR4 brings higher density DIMMs and once we have more mass production around the world as well as higher demand it will be a compelling upgrade. I *really* want to go with an E5 setup for my FreeNAS box (I want more than 32GB of RAM) but I'm going to hold out for next year because DDR4 means higher density modules that, in theory, will be about double the density (or more) for the same price. ;)

 

[joeschmuck]

You said you upgraded both FreeNAS and Plex... What have you done to isolate the cause? Have you reverted to the older PLEX version? Have you reverted to the older FreeNAS version?

I don't see this as a hardware issue if everything was working fine before you upgraded. Sure, the software could have become more demanding but it shouldn't have knocked you out from 3 streams to no streams.

If you want to save some power, remove half your RAM and one CPU. I have no idea why you have that kind of system for three hard drives. Just a suggestion.

 

[TremorAcePV]

-snip-

Then that makes more sense. Even with Plex, there is something weird going on. I could easily watch videos in Chrome using their experimental HTML5 player just fine. Now, if I try to use that, it fails. It basically buffers indefinitely, and it's certainly getting the data. In fact, Youtube had the same issue, so it might've been a Chrome thing. No idea. Very weird. But unrelated regardless.

I'll probably wait as long as I can. Who knows? Maybe the next update will fix it. Either way, I'll be looking for a DDR4 compliant equivalent to the C2550D4I. I like small, powerful, and efficient when I can get it.

You said you upgraded both FreeNAS and Plex... What have you done to isolate the cause? Have you reverted to the older PLEX version? Have you reverted to the older FreeNAS version?

I don't see this as a hardware issue if everything was working fine before you upgraded. Sure, the software could have become more demanding but it shouldn't have knocked you out from 3 streams to no streams.

If you want to save some power, remove half your RAM and one CPU. I have no idea why you have that kind of system for three hard drives. Just a suggestion.

In reverse order,

• Minecraft server & simply future potential expansion. This was before I knew about FSB and it's detriments. Don't worry, my MC server has been off for a few weeks this, so it's unrelated to all this.
• Well, that's the thing. 3 streams meant streaming to a PS3, a Phone, and my computer. Now, I can stream to PS3 & Phone somewhat fine. It's the computer that's pretty much horrible. The other devices buffer rarely, but before they didn't buffer at all. It's a huge difference.
• I haven't done either yet. That's why I've been trying to figure it out based on what information I have now. I don't have much experience administering a FreeNAS system or Jails via CLI which is what is required to install an older version of Plex since it downloads the latest version when the install happens.
  
  I know that'd be the best, fastest way to figure it out, but I just arrived at that step since I couldn't find the problem out yet. Still trying to figure out how to install an older version of Plex.

... I might have to come back to this tomorrow. :| Will update then.

 

[TremorAcePV]

@cyberjock @joeschmuck

I just thought I'd let you know it turns out my issue was with my computer somehow.

Jumping back to FreeNAS 9.2.1.5 didn't fix it, and neither did having an older version of Plex (as it installed automatically with the plugin). A reinstall of the OS fixed all my problems. I mean the computer I was using to access Plex, not the server itself.

Sorry for wasting your time.