On Tue, 9 Dec 2003, Jeremy Sonander wrote:
Hi Lothar,
This sounds interesting. Can you tell me how to control when in the boot process DMA is turned on? On running multiuser mode you can switch on/off the DMA via hdparm every time.
/sbin/hdparm -d /dev/hde # get the actual mode. /sbin/hdparm -d 1 -X udma2 /dev/hde # set to UDMA mode 2 (ON) hdparm -d 0 /dev/hdem # unset DMA mode (OFF) This to have in the boot process is comfort. There is the booting script /etc/init.d/boot.idedma what has an effect if the variable in /etc/sysconfig/hardware is set to a value. If this one is empty, then the script is exiting without an action for switching on/off DMA mode. SuSE default is empty value I did see. Please look in the file hardware: # # DEVICES_FORCE_IDE_DMA="/dev/hdc:off /dev/hdd:off /dev/hde:udma2" DEVICES_FORCE_IDE_DMA="" # I created a new variable for idedma boot script DEVICES_FORCE_IDE_DMA_NEW="/dev/hde:udma2" The value can you change in YAST. I take the ascii variant from yast only for the because in GUI the computer hangs an destroy the Reisefs on SATA-Harddisk. SATA = serial ATA. And if the boot procedure switch on DMA before hwscan then my maschine hangs and I get many harddisk errors. And on the other hand my laptop ASUS L3800C works via boot.idedma before hwscan. I have no idea what is wrong by SuSE-Software or Linux-Kernel 2.2.21-149 default or Shuttle-BIOS or SATA-HD! !!!!!!!!!!!!!!!!!!!!WARNING!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!! Here is a warning by SuSE company also. And my warnings are: Please do experiments only, if you had saved your data before and when you can handle the CD-Rom rescue system to switch off the DMA in the file /etc/sysconfig/hardware, if the computer hangs. By using Reiserfs I have to install SuSE new always. If there is one root partition only (SuSE-default) then you lost all user data also!!! I use from now ext2 and ext3 file system. There I don't lose any data. !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Under root you can do experiments via "hwparm" to see wether disk can DMA generally. See man page for hwparm and aministration handbook for init scripts and runlevels. By me runs principally the boot.idedma after hwscan. I did change the boot procedure manually by editing the dependend scripts how hwscan, xdm and new boot.idedma, by me named as idedma. Here I did insert the new sysconfig variable. After edit the scripts I did execute the command "insserv boot_script" for the changed boot scripts to make the right links automatically for you. Have a good success! Gruss Lothar Hansche, Germany, Berlin