Ubuntu
linux-source-2.6.19 package

hard disk speed regression (DMA is off)

Bug #72255 reported by Tormod Volden on 2006-11-17

This bug report is a duplicate of: Bug #71318: mkinitramfs doesn't include new pata drivers that switched from ide. Edit Remove

Affects		Status	Importance	Assigned to	Milestone
	linux-source-2.6.19 (Ubuntu)	Confirmed	High	Unassigned

Bug Description

I am running 2.6.19-6-generic on an otherwise clean Edgy install. Everything feels slower, the mouse pointer is jerky, and booting time is slower (104s vs 64s).

Disk access (buffered) is slower in 2.6.19:
$ sudo hdparm -Tt /dev/hda
/dev/hda:
Timing cached reads: 616 MB in 2.00 seconds = 307.81 MB/sec
Timing buffered disk reads: 4 MB in 3.41 seconds = 1.17 MB/sec

versus 2.6.17:
$ sudo hdparm -Tt /dev/hda
/dev/hda:
Timing cached reads: 596 MB in 2.00 seconds = 297.95 MB/sec
Timing buffered disk reads: 50 MB in 3.04 seconds = 16.46 MB/sec

I have a SAMSUNG MP0804H, ATA DISK drive.

Revision history for this message

Tormod Volden (tormodvolden) wrote on 2006-11-17:

lspci output Edit (971 bytes, text/plain)

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Tormod Volden (tormodvolden) wrote on 2006-11-17:

(I am booting with init=/bin/bash to avoid any background activity.) Turning off DMA in .17 (hdparm -d0) gives the same speeds as in .19. hdparm -d in .19 reports 0 (off). Trying to enable it with hdparm -d1 gives:
HDIO_SET_DMA failed: Operation not permitted

Revision history for this message

Nikolai Prokoschenko (nikolai) wrote on 2006-11-17:

I can confirm this behaviour - with exactly the same errors.

Tormod Volden (tormodvolden) on 2006-11-17

Changed in linux-source-2.6.19:
status:	Unconfirmed → Confirmed

Ben Collins (ben-collins) on 2006-11-20

Changed in linux-source-2.6.19:
importance:	Undecided → High

Revision history for this message

Eungkyu Song (eungkyu) wrote on 2006-11-20:

This may be related to bug #71318.
Please read my last two comments,
https://launchpad.net/distros/ubuntu/+source/linux-source-2.6.19/+bug/71318/comments/11
https://launchpad.net/distros/ubuntu/+source/linux-source-2.6.19/+bug/71318/comments/12

Add pata_via line to /etc/initramfs-tools/modules,
sudo update-initramfs -u,
and reboot.

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Tormod Volden (tormodvolden) wrote on 2006-11-20:

Thanks a lot, Eungkyu! I added the pata_via to /etc/initramfs-tools/modules and ran sudo update-initramfs -u -k 2.6.19-6-generic (I was running this on another kernel). Additionally I had to change root=/dev/hda2 to root=/dev/sda2 in /boot/grub/menu.lst since my install is not transitioned to UUID yet. Now it runs fast and nice!