Problem with timeshift files mutiplying on channel change (while recording) (1 Viewer)

[Owlsroost]

TV-Server Version: 1.0 SVN 21720
MediaPortal Version: 1.0 SVN 21720
MediaPortal Skin: Blue 3 wide
Windows Version: Vista Home Basic SP1
CPU Type: Intel E4500, 2.2GHz
HDD: 500GB
Memory: 2GB
Motherboard: Dell Vostro 200SL
Video Card: XFX 9500GT low-profile
Video Card Driver: 181.20
Sound Card: Creative SoundBlaster Audigy SE
Sound Card AC3: Creative SoundBlaster Audigy SE
Sound Card Driver: P17X_PCDVT_LB_1_04_0079
1. TV Card: Kworld DVB-T 399U
1. TV Card Type: DVB-T
1. TV Card Driver: V8.4.28.1
2. TV Card:
2. TV Card Type:
2. TV Card Driver:
3. TV Card:
3. TV Card Type:
3. TV Card Driver:
4. TV Card:
4. TV Card Type:
4. TV Card Driver:
MPEG2 Video Codec: PDVD7
MPEG2 Audio Codec: FFDShow (libavcodec)
h.264 Video Codec: MPC-HC
Satelite/CableTV Provider:
HTPC Case:
Cooling:
Power Supply:
Remote: USB-UIRT -> EventGhost
TV: Panasonic TX37LZD80 @ 1920x1080p
TV - HTPC Connection: DVI -> HDMI

I have a twin-tuner DVB-T setup.

If MP is recording from a channel, and I then skip between viewing a channel on a different DVB-T 'mux' and one on the same (as the recording) DVB-T 'mux', the TV-server doesn't appear to delete/re-use the timeshift buffer files for the tuner being used for the recording - it keeps creating new ones (until the small 256MB ramdisk I use for timeshifting runs out of space, when the 'live' TV just freezes). It looks like all of the 'sets' of timeshift files are being actually being updated (the file modification times stay in step).

Logs and screenshot of the timeshift disk files attached.

TV-server is configured to use a maximum of 3 x 20MB timeshift files per tuner (the minimum possible settings), the timeshift files are stored on a 256MB ramdisk.

The problem is completely repeatable:

start MP -> start TV -> manually start recording on current channel -> switch to channel on different DVB-T mux -> switch to channel on same mux as recording -> (repeat last 2 steps a few times) -> result is multiple sets of timeshift files e.g. live1-0.ts.*/live1-2.ts.*/live1-3.ts.* etc all being continually updated (I've never noticed a 'live1-1.ts.*' set created - it always starts with 'live1-0.ts.*' then creates a 'live1-2.ts.*' set next).

Tony

(and yes, the thread title has a spelling mistake.....)

 

[ronilse]

Hi,
Yeah it's the same issue as we see & it's already in Mantis

Regards
Roy

 

[Owlsroost]

OK, thanks - I'd searched the forum but not Mantis.

The description in Mantis isn't quite the same behaviour - once MP has been closed, I can delete all the timeshift files, in fact when the recording and live TV have both stopped I think the extra/spurious timeshift files are deleted by MP - but I agree that my issue is almost certainly another manifestation of the same bug.

Tony

 

[gibman]

It's quite an old bug in fact.

I'll try and explain.

On any DVB card the directshow graph is basically either running or stopped.

Obviously when the DVB card is tuned into a channel (rec. or timeshifting), then the graph is running, otherwise it's stopped (no activity).

The problem is that MP will keep on adding timeshifting files/sessions to the card as long as it is already running.
Once the DVB graph on that specific card is stopped, then all TS files are removed. And the graph will only stop when all channels on the card are ceased.

As u can see this will eat away CPU / HD and CAM resources on these "ghost" channels that are no more active.

Maybe tswriter should be notified when a sub channel is stopped and then remove it internally ?

/gibman

 

[Owlsroost]

Maybe tswriter should be notified when a sub channel is stopped and then remove it internally ?

/gibman

Sounds like a good idea.

Something needs to be done about the issue, otherwise it's impossible to determine in advance the maximum disk space the timeshift files need (as well as wasting CPU/disk bandwidth).

Tony

 

[doveman]

Not trying to hijack this thread, but I seem to be having a similar problem with svn 21813, where MP is trying to create more ts files on channel change (no recordings in progress) and can't cope with the fact that the max number of files I've set (3) already exist: https://forum.team-mediaportal.com/1-0-final-svn-builds-302/livetv-freezing-55764/

I never experienced this problem in earlier builds. I'm going to try raising the max number of files and reducing the filesize to see if that helps.

 

[Owlsroost]

doveman - can you add your system specs to your user profile (and make sure they are visible to other users i.e. so that you have a 'My System' pop-up to the left of your posts).

A few comments:

1. The number of timeshift files is per tuner, so if max files = 3, a twin-tuner setup can create up to six buffer files, three for each tuner.

2. A channel change on the same tuner should not create more timeshift buffers - it should re-use the existing files (or at least delete the old ones). If it swaps to a different tuner it will create a new set for that tuner if they don't already exist.

3. The bug I reported is specific to the situation where a recording is already in progress, and results in continually updated multiple sets of files, 'attached' to the tuner being used for the recording.

I've just installed SVN 21813 - I'll see what happens with my setup....

Tony

 

[doveman]

Sorry about that, didn't realise that system specs aren't visible by default. Should be fixed now.

Thanks for the tip about the number of timeshift files. I do have a twin-tuner setup, so I'll set the filesize to 40MB, which will allow 6 files to fit on my 256MB ramdisk and see if that fixes the problem. Not sure if MP was trying to use the 2nd tuner but I wouldn't have thought it needed to when just changing channel. There was enough free space for MP to create a new ts file when I had the filesize set to 80MB though, so I'm not sure why it couldn't.

I've done some more experimenting which might be of interest, but I'll post about that in my own thread.

 

[tompa]

Hi!

So why doesn't this happens when NOT running RTSP? I do see the problem with RTSP and multiseat, but not without.

/tompa

edit: running dedicated server.

 

[Mr Hipp]

Hi

I see the problem on a single seat installation.

Mr Hipp