Paul Smith a écrit :
> On 8/28/06, Brian Chadwick <brianchad@xxxxxxxxxxxxxx> 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
> #
What is exactly your problem? Do you have SATA HD? Is it a laptop?
--
François Patte
UFR de mathématiques et informatique
Université Paris 5 - Paris
http://www.math-info.univ-paris5.fr/~patte
