Why do DVD players acces the HD constantly?

[Tequila]

Sorry for the dumb question but you know how it goes... too much to learn out there. I downloaded and installed the Ogle DVD player which works incredibly well on my linux machine. I noticed though that when I'm playing a DVD with it that it it's constantly accessing my hard drive.. the HD led is chugging away the whole time. If I pause it goes away. My DVD and HD are on separate controllers and the HD led is in no way cross connected to the DVD led :)

I have 384MB of ram and just wondering why this happens. I've got tons of free memory so why do DVD players access the HD drive so much? I noticed this with a few other dvd players as well so it's not just Ogle.

[sarah31]

just a guess but i would assume that it is a part of the transfer/translation process. Likely data is taken from the dvd and is passed to the memory and files on the hd are constantly being used to translate the data.

[danrees]

Have you hdparm'd your hard drive and DVD drive? Read up on the subject first, but if you've got a recent motherboard and hard drive then the following should speed things up:

/sbin/hdparm -c1 -d1 /dev/hda
/sbin/hdparm -c1 -d1 /dev/hdd (or whatever your DVD drive is)

[Tequila]

Yep both the HD and DVD drives are already set up for dma and 32-bit transfer using hdparm like your example.

Any other ideas? :)

[mdwatts]

The Linux DVD players use the HD as a buffer so to speed up the playing of dvd's and to ensure a smooth playback.

[Flowbs]

Originally posted by Tequila
I noticed ... that when I'm playing a DVD with it that it it's constantly accessing my hard drive.. the HD led is chugging away the whole time. If I pause it goes away. My DVD and HD are on separate controllers and the HD led is in no way cross connected to the DVD led :)

I'm curious, next time you play a DVD open an x-term and run dmesg. Do you get a repeating error message to the effect of . . .

hdc: packet command error: status=0x51 { DriveReady SeekComplete Error }
hdc: packet command error: error=0x54
ATAPI device hdc:
Error: Illegal request -- (Sense key=0x05)
Cannot read medium - incompatible format -- (asc=0x30, ascq=0x02)
The failed "Read Subchannel" packet command was:
"42 02 40 01 00 00 00 00 10 00 00 00 " ???

[mdwatts]

That's right. I forgot about Xine doing quite a bit of logging.

You can try starting Xine and send the output to /dev/null.

[Flowbs]

Xine may or may not cache to the hard drive, I don't know. Since my hard drive begins chugging the minute I insert a Movie DVD into my DVD drive before I run Xine or any other player, I suspected (at least for me) cacheing was not the issue. After Googling this around a bit I suspected it was a kernel thing. I found an excellent Xine video HowTo that appears to confirm this.

From Xine Video Player HOWTO: http://dvd.sourceforge.net/xine-howto/en_GB/html/howto-10.html#ss10.9

10.9 Using Linux, I get an error which contains status=0x51 { DriveReady SeekComplete Error }

To fix this error, try enabling `Use multi-mode by default' in your kernel (re-compile setting ATA/IDE/MFM/RLL support -> IDE, ATA and ATAPI Block devices -> Use multi-mode by default to `Y'). The relevant piece of kernel documentation states:

CONFIG_IDEDISK_MULTI_MODE:

If you get this error, try to say Y here:

hda: set_multmode: status=0x51 { DriveReady SeekComplete Error }
hda: set_multmode: error=0x04 { DriveStatusError }

If in doubt, say N.

Soo it looks like a kernel recopmpile may fix the issue. I say may because I don't plan on doing the recompile. I've recompiled many kernels but I find the 1st reccompile in a new distribution is the toughest since you don't have a good .config file to use and so have to check every little option; inevitibly leaving out something. Since the 2.4 kernel is developing more slowly than past kernels, I can get the Red Hat kernel.rpms and they are up to date. Used to be if you wanted the newest stable kernel you would need to bop on over to kernel.org and get it there.



Originally posted by Flowbs


I'm curious, next time you play a DVD open an x-term and run dmesg. Do you get a repeating error message to the effect of . . .

hdc: packet command error: status=0x51 { DriveReady SeekComplete Error }
hdc: packet command error: error=0x54
ATAPI device hdc:
Error: Illegal request -- (Sense key=0x05)
Cannot read medium - incompatible format -- (asc=0x30, ascq=0x02)
The failed "Read Subchannel" packet command was:
"42 02 40 01 00 00 00 00 10 00 00 00 " ???

[Tequila]

Sorry for the lack of updates, I totally forgot about this thread. Ok a couple of things. In my custom kernel I already had "Use Multi-mode by default" checked to Y so that rules out that possibility.

I'm curious, next time you play a DVD open an x-term and run dmesg. Do you get a repeating error message to the effect of

Nope, I only get an error like that if I accidentially try to read a DVD using my CD player. Otherwise when I use Ogle to play a DVD I get no error messages whatsoever.

So, I guess I'll have to live with it. My concern is the wear and tear on the HD otherwise everything else is fine with it.

Thanks for your replies.

[Flowbs]

Originally posted by Tequila
I'm curious, next time you play a DVD open an x-term and run dmesg. Do you get a repeating error message to the effect of

Nope, I only get an error like that if I accidentially try to read a DVD using my CD player. Otherwise when I use Ogle to play a DVD I get no error messages whatsoever.

Hmm, interesting. Since I run a DVD and a burner, the symlinks for both /dev/cdrom and /dev/dvd point to /dev/hdc. Think I'll try removing the link to /dev/cdrom and edit /etc/fstab to see if I still get the HD chugging.