[vdr] Re: Big Problem with playing DVD's

[Andreas Schultz <aschultz@cs.uni-magdeburg.de>]

Hi Holger,

Sorry for not answering earlier,

On Tuesday 23 April 2002 17:14, Holger Wagner wrote:
> Hello,
>
> this is my second try with my DVD-problem.
>
> First time nobody resonse to my question. I hope, this time somebody can
> help me with my DVD-Problem.
>
> I have four DVD's (Tremors 1; Tremors 2; Der Schuh des Manitu and Miss
> Undercover)

i have tried the last two recently on my system and they did work normaly,  
the problem has probably something do to with your setup.

> All four are the German Versions and with all four replay is not smooth.
>
> DVD frozen every few seconds for millisecond.
> Audio and Video stucks every few seconds.
> On a "normal" DVD-Player all four DVD's plays smooth.
>
> My Linux-VDR:
> Duron 800Mhz, DVD 16x , Suse 7.2 , Kernel 2.4.4
> 2x Hauppauge DVB-S 2.1 ,VDR 1.0.0 with AIO 17.04.02 and the DVB-Driver
> Siemens_dvb-0.9.4-2002-04-01.tgz from Klaus Schmidinger's site.

Did you also try it with only one of the DVB cards pluged in? Also swap them 
around to see wether there is a hardware problem. The kernel should be fine, 
but to be sure would it be possible to upgrade to 2.4.18?

> No problems with VDR record and replay only with DVD replay.
>
> DMA for the DVD-ROM-Drive is enabled.
>
> I have testet DVD-Speed with different hdparm -E Option's.
>
> hdparm -E1  Buffer-cache reads 193 MB/sec, disk reads 3,51 MB/sec /dev/dvd
> hdparm -E4  Buffer-cache reads 193 MB/sec, disk reads 3,51 MB/sec /dev/dvd
> hdparm -E16 Buffer-cache reads 193 MB/sec, disk reads 3,51 MB/sec /dev/dvd
> hdparm -E48 Buffer-cache reads 193 MB/sec, disk reads 3,51 MB/sec /dev/dvd

that should be fine

> No change with different -E parameter.
>
> I have copyed the complete DVD on my harddisk and have link /dev/hda with
> /dev/dvd . With replay DVD from my harddisk same problem, the replay stucks
> every few seconds.

that proves that the dvd drive is not the problem

To check wether this a speed problem or not, you could this patch:

--- 1.3/ringbuffer.c    Mon Apr 22 12:34:03 2002
+++ edited/ringbuffer.c Tue Apr 23 18:08:26 2002
@@ -290,8 +290,10 @@
   Lock();
   cFrame *p = head ? head->next : NULL;
   Unlock();
-  if (!p && Wait)
+  if (!p && Wait) {
+     fprintf(stderr, "%10d: RingBufferFrame empty\n", time_ms());
      WaitForGet();
+  }
   return p;
 }

During menues and other intro sequences empty buffers are normal, but they 
should not occure during the main feature after the initial first few 
seconds.

Andreas