Hdparm

hdparm is used in Linux for setting harddisk options.

To view current settings, simply run: hdparm /dev/hda (or /hdb, /hdc, etc.)

-c1 enables 32-bit I/O -d1 enables DMA -X66 enables ATA/33

PIO mode 	Switch 	Burst Rate 0 	-X08 	3.3MB/sec 1 	-X09 	5.2MB/sec 2 	-X10 	8.3MB/sec 3 	-X11 	11.1MB/sec 4 	-X12 	16.7MB/sec

MW DMA mode 	Switch 	Burst Rate 0 	-X32 	4.2MB/sec 1 	-X33 	13.3MB/sec 2 	-X34 	16.6MB/sec

UDMA mode 	Switch 	Burst Rate 2 (ATA/33) 	-X66 	33MB/sec 4 (ATA/66) 	-X68 	66MB/sec 5 (ATA/100) 	-X69 	100MB/sec

Red Hat uses /etc/rc.sysinit to call scripts /etc/sysconfig/harddiskhda, /etc/sysconfig/harddiskhdb, etc. to run hdparm upon boot.

File: /etc/sysconfig/harddiskhda:

USE_DMA=1

EIDE_32BIT=1

To enable DMA during boot, add the following line to your lilo.conf file:

append = "ide0=dma"


 * http://www.linuxdevcenter.com/pub/a/linux/2000/06/29/hdparm.html


 * http://support.intel.com/support/graphics/sb/CS-010515.htm