Re: Help with DVD+RW w/UDF file system

[Chris Oxenreider <oxenreid@state.net>]

I set the drives parameters to:
    hdparm -d1 -k1 -p4 -c1 /dev/hda

The doccumentation for the drive lists it as PIO mode 4 and DMA mode 2.

The listing of the parameters shows:
    hdparm -v /dev/hda

/dev/hda:
 HDIO_GET_MULTCOUNT failed: Invalid argument
 IO_support   =  1 (32-bit)
 unmaskirq    =  1 (on)
 using_dma    =  1 (on)
 keepsettings =  1 (on)
 readonly     =  0 (off)
 readahead    = 256 (on)
 HDIO_GETGEO failed: Invalid argument


When I do the 'cp' a typical vmstat  shows:
 r  b   swpd   free   buff  cache   si   so    bi    bo   in    cs us sy id wa
 0  0    244  10208  16156 222516    0    0     0    24 1208   819  0  0 0  100


Testing the speed shows:
    hdparm -t /dev/hda

/dev/hda:
 Timing buffered disk reads:   14 MB in  3.14 seconds =   4.46 MB/sec

Which is about 1mb slower than the DVD+RW 4x speed as listed in the
specifications sheet [1].

So far this has only manafesed when attempting to treat a DVD+RW with a
UDF file system as a removable hard disk.  Burning a CD-R (I have not
attempted to burn a DVD+R yet) works fine.

[1] http://www.samsung.com/Products/OpticalDiskDrive/DVDRRW/OpticalDiskDrive_DVDRRW_TS_H552U_sp.htm

On Mon, 5 Sep 2005, Bill Davidsen wrote:

> Chris Oxenreider wrote:
>
> > Hi,
> >
> > I have been trying to get DVD+RW w/UDF to work under Fedora Core 3
> > [Kernel  2.6.12-1.1372_FC3] using a Samsung TS-H552U DVD drive.
> > I have formatted the disk, I have put a UDF file system on the disk, and
> > I have removed it from the automounter.
> >
> > I can copy small files [<1mb] to the disk fine.  I can 'rm' the files
> > fine.  However when copying large [>1gb] files to the DVD is painfully
> > slow, and the load average on my Athalon system jumps to 3.87 or higher.
> > The intention was to use the 4.3 Gb of DVD space as archive for my
> > flexbackup files of my home systems however this may be too slow.
> >
> > Any thoughts as to what I am doing wrong here?
> Is all the time system? Does hdparm show the drive as DMA enabled? If it is 
> running uning PIO it will take a great deal of CPU.

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Christopher G. Oxenreider  | Die Gedanken Sind Frei
chris.oxenreider@state.net |        -- Deutsches Volkslied
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