[gentoo-dev] SATA disk slower as /dev/sda then as in /dev/hda

[Mivz]

Hello,
I have a Intel SATA controler in my laptop and it is adressed as
/dev/sda. My cdrom is /dev/hdc.
My cdrom drive I can configure with hdparm to use dma and 32-bit io and
it has a nice speed:

/dev/hdc:
 Timing cached reads:   1408 MB in  2.00 seconds = 702.55 MB/sec
 Timing buffered disk reads:    4 MB in  5.56 seconds = 736.64 kB/sec

I can not use hdparm to configure /dev/sda, also sdparm can not set
anything:

sdparm --set UDMA6=1 /dev/sg0
    /dev/sg0: ATA       HTS726060M9AT00   MH4O
change_mode_page: failed setting page: SAT pATA control

This happens with all options, also awre, arre and wce. The speed of
this disk:

/dev/sda:
 Timing cached reads:   1424 MB in  2.00 seconds = 711.96 MB/sec
HDIO_DRIVE_CMD(null) (wait for flush complete) failed: Inappropriate
ioctl for device
 Timing buffered disk reads:  114 MB in  3.00 seconds =  37.95 MB/sec
HDIO_DRIVE_CMD(null) (wait for flush complete) failed: Inappropriate
ioctl for device

Now I tryed a old Gentoo 1.4-rc1 livecd, cause this one loads the disk
still as /dev/hda and not sda.
After enabling dma, 32bit io and udma: hdparm -X66 -c1 -d1

It had a speed of 2560.00 MB/sec bufferd
and 37,65 unbufferd.

It was almost 4 times as fast.

Why is it that when I use the new kernel SATA drivers and load is as
/dev/sda it is slower as with the old IDE drivers?

Mivz
-- 
gentoo-dev@g.o mailing list