Using ATA/EIDE drives with RedHat 3

[Michael Ault]

I am attempting to increase the PIO bus speed from 33
to 133 and to turn on DMA using ATA/EIDE drives. I
used to be able to do this with the idebus seeting and
the hdparm command. SO far I have not been able to
achieve this I get:

[root at aultlinux3 ~]# hdparm -X66  -d1 -u1 -m16 -c3
/dev/hdd

/dev/hdd:
 setting 32-bit IO_support flag to 3
 setting multcount to 16
 setting unmaskirq to 1 (on)
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Operation not permitted
 setting xfermode to 66 (UltraDMA mode2)
 multcount    = 16 (on)
 IO_support   =  3 (32-bit w/sync)
 unmaskirq    =  1 (on)
 using_dma    =  0 (off)

When I try. I have also tried adding the options lines
for the various drivers (ide1, ata_piix, libata) but
it seems to have no affect. 

Anyone been able to set up DMA for ATA/EIDE drives or
to set the bus speed in RedHat 3.0 release 4?

On loder, slower drives I was able to get speed up to
14.92 mb/sec using these methods, on these newer,
faster drives I can only get to 5.1 mb/sec

On Old RedHat:

[root at aultlinux2 root]# hdparm -m16 -c3 -X mdma2 -d1
-a8 -u1 /dev/hdb

/dev/hdb:
 setting fs readahead to 8
 setting 32-bit IO_support flag to 3
 setting multcount to 16
 setting unmaskirq to 1 (on)
 setting using_dma to 1 (on)
 setting xfermode to 34 (multiword DMA mode2)
 multcount    = 16 (on)
 IO_support   =  3 (32-bit w/sync)
 unmaskirq    =  1 (on)
 using_dma    =  1 (on)
 readahead    =  8 (on)
[root at aultlinux2 root]# hdparm -Tt /dev/hdb

/dev/hdb:
 Timing buffer-cache reads:   128 MB in  1.56 seconds
= 82.05 MB/sec
 Timing buffered disk reads:  64 MB in  4.29 seconds =
14.92 MB/sec

On New improved RedHat with newer, faster drives:

[root at aultlinux3 ~]# hdparm -X66  -d1 -u1 -m16 -c3
/dev/hdd

/dev/hdd:
 setting 32-bit IO_support flag to 3
 setting multcount to 16
 setting unmaskirq to 1 (on)
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Operation not permitted
 setting xfermode to 66 (UltraDMA mode2)
 multcount    = 16 (on)
 IO_support   =  3 (32-bit w/sync)
 unmaskirq    =  1 (on)
 using_dma    =  0 (off)
[root at aultlinux3 ~]# hdparm -tT /dev/hdc

/dev/hdc:
 Timing cached reads:   3820 MB in  2.00 seconds =
1909.34 MB/sec
 Timing buffered disk reads:   16 MB in  3.11 seconds
=   5.15 MB/sec

 
This is using the SATA drive (can't set it using
hdparm) as the boot drive with two EIDE drives chained
off of IDE1.

Thanks.

Mike Ault 

Michael R. Ault
Senior Consultant
Burleson Oracle Consulting
770-754-9057
www.ault.cc
www.remote-dba.com