dma on as default

[Paul Smith]

On 8/28/06, Brian Chadwick <brianchad at westnet.com.au> wrote:
> >> > Is there some way to  make permanent/default the change operated by
> >> > '/sbin/hdparm -d1 /dev/dvd', i.e., choosing dma on as default?
> >> >
> >> the best setting is very often selected automatically ... what version
> >> of fedora are u using?
> >>
> >> do hdparm -i /dev/hdx ... and have a look at the dma modes ... the
> >> current mode is indicated by a *
> >>
> >> u only need to use hdparm if that highest dma mode is not the current
> >> setting
> >
> > Thanks, Brian. I am using FC5. And
> >
> > # /sbin/hdparm -i /dev/dvd
> >
> > /dev/dvd:
> >
> > Model=_NEC DVD_RW ND-3520A, FwRev=1.04, SerialNo=
> > Config={ Removeable DTR<=5Mbs DTR>10Mbs nonMagnetic }
> > RawCHS=0/0/0, TrkSize=0, SectSize=0, ECCbytes=0
> > BuffType=unknown, BuffSize=0kB, MaxMultSect=0
> > (maybe): CurCHS=0/0/0, CurSects=0, LBA=yes, LBAsects=0
> > IORDY=yes, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
> > PIO modes:  pio0 pio1 pio2 pio3 pio4
> > DMA modes:  mdma0 mdma1 mdma2
> > UDMA modes: udma0 udma1 udma2
> > AdvancedPM=no
> >
> > * signifies the current active mode
> >
> > #
> >
> > And now?
> >
> hmmm......i have never seen hdparm not return a current mode ... intriguing.
>
> anyway ... the permanent way to save the changes is to put a command in
> your /etc/rc.d/rc.local file
>
> edit that file and at the end of the file put in "/sbin/hdparm /dev/hdx
> -your-parameters"
>
> from the output of hdparm i would try "/sbin/hdparm /dev/hdx -d1 -m32 -X
> udma2" where hdx is like hdc or hdd .. whichever device /dev/dvd is
> linked to. i suppose using a symbolic link (dvd) to the real drive is ok
> ... but i like to directly address the device
>
> that is the highest performance the drive will support ... what it means
> is ... use dma, and use 32 bit access, and use udma2 dma mode. If the
> drive does not perform properly with that setting, progressivley try
> less aggressive settings....eg. -X udma1, -X udma0, -X mdma2, ... etc
>
> you are using a recent motherboard chipset, so i doubt you will need to
> reduce the settings from what i have suggested .. though i must say i am
> perplexed that hdparm has not indicated a current mode ...

Put the line

/sbin/hdparm /dev/hdf -d1 -m32 -X udma2

in /etc/rc.d/rc.local, and then

the line

/sbin/hdparm /dev/hdf -d1

but after a reboot, in both cases, I get

# /sbin/hdparm /dev/dvd

/dev/dvd:
 IO_support   =  0 (default 16-bit)
  unmaskirq    =  1 (on)
 using_dma    =  0 (off)
  keepsettings =  0 (off)
  readonly     =  0 (off)
  readahead    = 256 (on)
 HDIO_GETGEO failed: Inappropriate ioctl for device
#

Paul