Can my server handle being a TV server? (1 Viewer)

[ears]

Hi,

I'm still having problem after problem with MediaPortal. I'm trying to work through the issues myself but need to know if I'm banging my head against a brick wall.

So simple question - should an HP Proliant microserver be able to cope with MediaPortal TV Server? A different PC does the TV watching.

I'd had issues with Windows Server 2012 with loads of discontinuities, and in the end tracked them down to when VMs were running in Hyper-V. When I turn the VMs off, performance is better but still far from perfect. I've had lots of recordings just stop for no apparent reason half way through. Still enough discontinuities for the recordings that do complete to be unwatchable. Pretty much the same thing on Windows 8 and Windows Server 2012. I've disabled all Windows Defender, antivirus etc. Recordings and live TV streaming work perfectly from DVBViewer Recording Service.

So back to my original point - is the server just not up to the job?

 

[mm1352000]

Okay, so lets recap.

First you said that only one of your tuners - the PCTV T2 tuner - was affected. Now it is all of them, right?
Previously you were running a custom build of TV Server that I'm aware has higher potential for stream discontinuity issues. Are you still using that custom version?

In your previous thread I said to ensure that you hadn't got any scanners operating on your timeshift/record folders. The more general thing I could have said is that discontinuities can be caused by HDD stress. In other words, if TV Server doesn't have fast enough read/write performance from your HDDs then you'll see discontinuities... and if you're using the same timeshift and record folders for all tuners and the same programs are running concurrently then you should see the same problem for all tuners.

Now, two other interesting points.

First, as far as I'm concerned you've proved that the HDD access speed is the issue with your comment about the VMs. I suspect their HDD access requirements are in conflict with TV Server. In other words, other applications running at the same time as TV Server that use the HDD heavily (like a scanner) or for random access (like a VM) can slow the HDD access enough to cause problems for TV Server. If you're running TV Server itself in a VM then that could also explain the problem.

Second, as far as I'm aware DVBViewer doesn't enable timeshifting by default when playing/streaming TV. In practical terms that means it is not hitting the HDD. MediaPortal does use the HDD for playing/streaming TV, and there is no way to disable it. This could explain why you have no problem with DVBViewer while you do have problems with MediaPortal.

So simple question - should an HP Proliant microserver be able to cope with MediaPortal TV Server? A different PC does the TV watching.

I don't think it is such a simple question - at least not for me.
At this point your HDD access speed seems the likely cause of the problem, but I'm not sure whether your low power CPU could also be a contributor. I advise you to open up task manager, jump over to the performance tab, and into the resource monitor. Find out whether your CPU and/or HDDs are being driven to the wall when TV Server is timeshifting. Find out whether it is TV Server doing this by itself or whether other processes are also contributing.

Note that when you test, please use the standard version of TV Server (DJBlu's version uses the HDD more heavily) and I recommend to test from the "manual control" section of TV Server configuration.

 

[ears]

Thanks MM - I'd never considered hard disk capacity but this could definitely be the issue., I stress tested DVBViewer last night and although no discontinuities were logged in any recordings on the server, the client, on a different PC receiving an RTSP stream, suffered a lot of errors.

There are 4 different HDDs in the ProLiant so as an interesting test I could set different folders on different disks for different tuners and see if that makes any difference. The network connection is gigabit so don't think there's any limiting factor there.

I also installed TV Server on the client, with a 2x3ghz AMD core (can't quite remember the model) and 2gb memory. It worked seamlessly but was timeshifting to an SSD drive. I'd ruled that configuration out previously as the Titan skin seemed to prevent wake from S3, causing the machine to reset and risking interrupting recordings.

I've been monitoring processor usage on the ProLiant and while it's significant it's rarely above 60%. I hadn't considered HDD speeds before so hadn't actively looked to remedy that - I will have a look tonight though, thank you.

My other option is to keep the single seat config on my HTPC and play with PowerScheduler++ to at least prevent the machine going to sleep while mediaportal is running (not hard) but I'm still not happy that I won't see any BSODs - I got one when rewinding through a channel change between HD and SD channels in the timeshift file the other day.

If I do stick on the HTPC I'm going to have to work out how on earth to get the stubborn Skystar S2 PCI card that's in there working with MP. I only have one PCI-E slot available in the hTPC so can't bring both Blackgolds across, but will start another thread about that one!

Thanks for all your help.

 

[mm1352000]

...but I'm still not happy that I won't see any BSODs - I got one when rewinding through a channel change between HD and SD channels in the timeshift file the other day.

In case you aren't aware, BSODs indicate error conditions in drivers or low level OS components. They can be triggered incidentally by software like MP in specific conditions if the driver doesn't handle certain patterns of interaction or isn't robust. FF/RW through a channel change would be a good example of specific conditions that could disrupt the GPU and/or audio driver.

If you're seeing BSODs frequently I'd recommend to upgrade drivers... and if that doesn't help and you're seeing BSODs in specific use cases - for example, FF/RW - then consider changing codecs or using MP in a different way (eg. skip steps instead of FF/RW).

 

[ears]

Thanks, yeah I've thought about drivers but it's highly likely to be something to do with CCC and it's always a gamble installing a new version. I think their drivers are created by monkeys who've had their typewriters replaced by ZX Spectrums. At least it helps them get the keywords right.

I think I've seen an option somewhere in MP to reset the timeshift file on a channel change, that could be a viable option.

 

[Owlsroost]

I'm still not happy that I won't see any BSODs - I got one when rewinding through a channel change between HD and SD channels in the timeshift file the other day.

I agree with what mm said - the chances are it's the AMD drivers/video decoder hardware that isn't handling stream data errors properly in DXVA mode. If you have enough CPU performance you could try running LAV video decoder in software-only decode mode.

Re. the other Microserver problems - are you running software RAID etc. on the drives ?

Remember these are low-performance CPU's running on an old AMD motherboard chipset, basically intended to be used as cheap/small office fileservers (we have two N36L's in my work office, so I have some idea of their performance). I think some MP users are using them as TV servers, but you have a fairly fully-loaded system which might be a step too far.

Have you tried running an interrupt latency checker - might give you a clue as to what might be stalling things (and hence causing TV stream data from the tuners to be lost => discontinuity errors) ?

 

[ears]

Thanks Owlsroost I'm sure part of this is me just trying to push more than I can out of the server. When I bought it, I needed a NAS so bought that as it would do the job for not much more money and give me more versatility. But I think I'm getting carried away with it now and forgetting its limits, like you say. It's not in a RAID config so disk access will be a bit more bottlenecked.

I think I'm happy in the single seat config now. Response times from TV server are noticeably improved and discontinuities have been almost wiped out. I rather suspect that DVBViewer and MP process streams so differently that there's no point in comparing directly, especially now the number of discontinuities in MP is so low.

So I'm happy - thank you! After at least 3 abortive attempts over the last few years to switch to MP - I think this time it's worked. I've always wanted to use it - it's the only real one stop solution - DVBViewer is very good at TV but the interface and usability are lacking; XBMC is a good media centre but the TV interface and functionality are lacking.

And DJBlu's modification saves me so much time in channel and channel group organisation and EPG capture, it's the real icing on the cake.