[vdr] Vdr or driver performance dropout

[Kartsa]

Stefan Huelswitt kirjoitti:
> On 01 Feb 2007 Reinhard Nissl <rnissl at gmx.de> wrote:
>
>   
>> Heikki Manninen wrote:
>>
>>     
>>>> I've noticed that earlier when I was using PIII 550 MHz and vdr 1.3.22 
>>>> (or something about) I made a test by recording nine channels 
>>>> simultaneously and watching a recording at the same time. I remember 
>>>> there seemed to be no trouble doing it. Now when I have vdr 1.4.4 after 
>>>> fourth recording starts vdr becomes sluggish and there starts to come 
>>>> errors on log:
>>>> dvb-ttpci: warning: timeout waiting in LoadBitmap
>>>> when pushing menu button. And ofcourse no menu appears or menu appears 
>>>> only partly.
>>>>         
>>> Exactly the same thing here and with the latest and the second latest
>>> firmware. My FF 2.1 TT card starts to die after third simultaneous
>>> recording. But then again, I think that budget cards are much better in
>>> this area.
>>>       
>> Most likely, it's me who has to be blamed. Around 1.3.27, cVideoRepacker
>> was introduced which has an impact on CPU load. This could be a reason
>> why the menu is slow when running several recordings at the same time.
>>     
>
> I don't think that the problem is related to anything on VDR
> side.
>
> AFAIK the bandwidth from ARM to PCI bus is very limited on
> full-featured cards. With 3 recordings being transfered to VDR
> there is simply not enough bandwidth left for the OSD transfers.
> Hence the LoadBitmap timeout.
>
> I experience the problem since VDR introduced concurrent
> recordings and I cannot believe that there is any VDR / firmware
> combination which doesn't show this behaviour as it's IMO a
> hardware limitation.
>
> Budget cards doesn't have this limitation, they can transfer the
> full transponder without problems.
>   
I know the performance was better when I was using vdr-1.3.22. I know I 
had 9 recordings going on and still I was able to watch a previous 
recording and I was using a slower cpu and a ff card. Ofcourse my recent 
test does prove your point, hence the question "what is the best 
combination of hw and sw?".

\\Kartsa