2003-08-06 18:52:18

by Michael Buesch

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Subject: [2.6] system is very slow during disk access

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Hi.

I have massive problems with linux-2.6.0-test2.
When some process writes something to disk, it's very hard
to go on working with the system.

Some test-szenario:
$ dd if=/dev/zero of=./test.file

While dd is running, xmms skips playing every now and then
and the mouse is near to be unusable. The Mouse-cursor
behaves some kind of very lazy and some times it jumps
from one point on the display to another.
When I stop disk-access, it works again quite fine.

Would be cool, if you could give me some point to start
for tracking this down.

Please CC me, as I'm not subscribed to linux-ide. Thanks.
- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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2003-08-06 19:29:51

by Michael Buesch

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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On Wednesday 06 August 2003 20:51, Michael Buesch wrote:
> Hi.
>
> I have massive problems with linux-2.6.0-test2.
> When some process writes something to disk, it's very hard
> to go on working with the system.
>
> Some test-szenario:
> $ dd if=/dev/zero of=./test.file
>
> While dd is running, xmms skips playing every now and then
> and the mouse is near to be unusable. The Mouse-cursor
> behaves some kind of very lazy and some times it jumps
> from one point on the display to another.
> When I stop disk-access, it works again quite fine.
>
> Would be cool, if you could give me some point to start
> for tracking this down.
>
> Please CC me, as I'm not subscribed to linux-ide. Thanks.

I sould add some things:

I'm using ReiserFS.

I've made a test-run without X in the console now.
I started this program on tty0, to see if there are big skips or
something like that:

int main()
{
while (1) {
printf("jkhdsjklhfkjfhsdjkhjbghghjghjjh");
printf("jsdl?kflsm,dfowekcldfqw");
printf("JKjhdsjkfhsnsdjkhJhjkhjkbmnxbuihjknlk");
printf("kcjkld");
}
return 0;
}

When the machine isn't doing any disk-access, the "garbage-printing"
to the console, produced by the program above is very smooth.
But when I start dd on another tty, massive skips and breaks occur
to the output of the nice program above.
These are not small skips and breaks.
The system is quite unusable during running dd, because it doesn't
respond as it should.

I just tried to run the test-scenario on my other Linux-installation
on this machine with kernel 2.4.10 and there the output of the program
was quite smooth, even it dd was running und the system was still usable.

- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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2003-08-06 19:32:03

by Michael Buesch

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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On Wednesday 06 August 2003 21:29, Frank Van Damme wrote:
> Maybe you just didn't enable DMA on them. Use hdparm -v /dev/foo to find
> out.

DMA is on.

root@lfs:/home/mb> hdparm -v /dev/hda

/dev/hda:
multcount = 16 (on)
IO_support = 1 (32-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
readonly = 0 (off)
readahead = 256 (on)
geometry = 14244/16/63, sectors = 80418240, start = 0


root@lfs:/home/mb> hdparm -v /dev/hdc

/dev/hdc:
multcount = 16 (on)
IO_support = 1 (32-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
readonly = 0 (off)
readahead = 256 (on)
geometry = 14244/16/63, sectors = 80418240, start = 0


- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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2003-08-06 19:29:16

by Frank Van Damme

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

On Wednesday 06 August 2003 20:51, Michael Buesch wrote:
> Hi.
>
> I have massive problems with linux-2.6.0-test2.
> When some process writes something to disk, it's very hard
> to go on working with the system.
>
> Some test-szenario:
> $ dd if=/dev/zero of=./test.file
>
> While dd is running, xmms skips playing every now and then
> and the mouse is near to be unusable. The Mouse-cursor
> behaves some kind of very lazy and some times it jumps
> from one point on the display to another.
> When I stop disk-access, it works again quite fine.
>
> Would be cool, if you could give me some point to start
> for tracking this down.
>
> Please CC me, as I'm not subscribed to linux-ide. Thanks.

Maybe you just didn't enable DMA on them. Use hdparm -v /dev/foo to find out.

--
Frank Van Damme http://www.openstandaarden.be
~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"Je pense, donc je suis brevet?."

2003-08-06 20:47:29

by Michael Buesch

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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On Wednesday 06 August 2003 22:31, insecure wrote:
> hdparm -T -t output? dmesg? lspci? /proc/ide stuff?


root@lfs:/home/mb> hdparm -T -t /dev/hda

/dev/hda:
Timing buffer-cache reads: 128 MB in 0.37 seconds =343.22 MB/sec
Timing buffered disk reads: 64 MB in 1.53 seconds = 41.81 MB/sec


dmesg doesn't show any unusual messages.


root@lfs:/home/mb> lspci
00:00.0 Host bridge: Intel Corp. 82845 845 (Brookdale) Chipset Host Bridge (rev 04)
00:01.0 PCI bridge: Intel Corp. 82845 845 (Brookdale) Chipset AGP Bridge (rev 04)
00:1e.0 PCI bridge: Intel Corp. 82801BA/CA/DB PCI Bridge (rev 05)
00:1f.0 ISA bridge: Intel Corp. 82801BA ISA Bridge (LPC) (rev 05)
00:1f.1 IDE interface: Intel Corp. 82801BA IDE U100 (rev 05)
00:1f.2 USB Controller: Intel Corp. 82801BA/BAM USB (Hub #1) (rev 05)
00:1f.3 SMBus: Intel Corp. 82801BA/BAM SMBus (rev 05)
00:1f.4 USB Controller: Intel Corp. 82801BA/BAM USB (Hub #2) (rev 05)
01:00.0 VGA compatible controller: nVidia Corporation NV25 [GeForce4 Ti4400] (rev a2)
03:02.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11)
03:02.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11)
03:03.0 Multimedia audio controller: Ensoniq 5880 AudioPCI (rev 02)
03:04.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8029(AS)
03:0c.0 USB Controller: NEC Corporation USB (rev 41)
03:0c.1 USB Controller: NEC Corporation USB (rev 41)
03:0c.2 USB Controller: NEC Corporation USB 2.0 (rev 02)

root@lfs:/home/mb> cat /proc/ide/drivers
ide-cdrom version 4.59-ac1
ide-disk version 1.18

root@lfs:/home/mb> cat /proc/ide/hda/settings
name value min max mode
- ---- ----- --- --- ----
acoustic 0 0 254 rw
address 0 0 2 rw
bios_cyl 79780 0 65535 rw
bios_head 16 0 255 rw
bios_sect 63 0 63 rw
bswap 0 0 1 r
current_speed 69 0 70 rw
failures 0 0 65535 rw
init_speed 69 0 70 rw
io_32bit 1 0 3 rw
keepsettings 0 0 1 rw
lun 0 0 7 rw
max_failures 1 0 65535 rw
multcount 16 0 16 rw
nice1 1 0 1 rw
nowerr 0 0 1 rw
number 0 0 3 rw
pio_mode write-only 0 255 w
slow 0 0 1 rw
unmaskirq 0 0 1 rw
using_dma 1 0 1 rw
wcache 0 0 1 rw


root@lfs:/home/mb> cat /proc/ide/hda/model
IC35L040AVVA07-0


> --
> insecure

- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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2003-08-06 22:02:58

by Andrew Morton

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

Michael Buesch <[email protected]> wrote:
>
> I just tried to run the test-scenario on my other Linux-installation
> on this machine with kernel 2.4.10 and there the output of the program
> was quite smooth, even it dd was running und the system was still usable.

Please boot the 2.6 machine with "profile=1" on the kernel boot command line.

start the `dd', do a `readprofile -r', wait ten seconds, do

readprofile -m /wherever/System.map

then post the results.

Thanks.

2003-08-06 22:14:29

by Willy Gardiol

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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Try to unmask IRQ, this should realy help...
hdparm -u1 /dev/hda

I usually do on my disks:
hdparm -c1 -u1 -d1 -X69 /dev/hda
(note: use -X69 only for for an UDMA 100 or 133 drive)

> > Maybe you just didn't enable DMA on them. Use hdparm -v /dev/foo to find
> > out.
>
> DMA is on.
>
> root@lfs:/home/mb> hdparm -v /dev/hda
>
> /dev/hda:
> multcount = 16 (on)
> IO_support = 1 (32-bit)
> unmaskirq = 0 (off)
> using_dma = 1 (on)
> keepsettings = 0 (off)
> readonly = 0 (off)
> readahead = 256 (on)
> geometry = 14244/16/63, sectors = 80418240, start = 0
>
>
> root@lfs:/home/mb> hdparm -v /dev/hdc
>
> /dev/hdc:
> multcount = 16 (on)
> IO_support = 1 (32-bit)
> unmaskirq = 0 (off)
> using_dma = 1 (on)
> keepsettings = 0 (off)
> readonly = 0 (off)
> readahead = 256 (on)
> geometry = 14244/16/63, sectors = 80418240, start = 0

- --

!
Willy Gardiol - [email protected]
gardiol.eu.org
Use linux for your freedom.

"La guerra non far? mai finire
alcuna guerra, nel migliore dei
casi sar? stata una guerra in pi?."

Gino Strada, Buskash?

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2003-08-06 22:29:39

by Michael Buesch

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Subject: Re: [2.6] system is very slow during disk access

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On Thursday 07 August 2003 00:19, Willy Gardiol wrote:
> Try to unmask IRQ, this should realy help...
> hdparm -u1 /dev/hda
>
> I usually do on my disks:
> hdparm -c1 -u1 -d1 -X69 /dev/hda
> (note: use -X69 only for for an UDMA 100 or 133 drive)

Thanks, -u1 -X69 helps a bit, but the core-problem is still
there. The system still doesn't respond as it should.
It's better, but it's not good.

I'll try to profile, as Andrew said.

- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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2003-08-06 22:46:17

by Michael Buesch

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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On Thursday 07 August 2003 00:04, Andrew Morton wrote:
> Please boot the 2.6 machine with "profile=1" on the kernel boot command
> line.
>
> start the `dd', do a `readprofile -r', wait ten seconds, do
>
> readprofile -m /wherever/System.map
>
> then post the results.

I've done this twice and appended the results to this mail.



But I've captured a few other interesting things in the syslog.
After doing a
$ hdparm -c1 -u1 -d1 -X69 /dev/hda
I saw this in my syslog:

Aug 7 00:32:05 lfs kernel: blk: queue c049195c, I/O limit 4095Mb (mask 0xffffffff)
Aug 7 00:32:05 lfs kernel: hda: Speed warnings UDMA 3/4/5 is not functional.

The onboard IDE controller is a UDMA-100 controller
and the disks do run in this mode, too.

- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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Subject: Re: [2.6] system is very slow during disk access


On Thu, 7 Aug 2003, Michael Buesch wrote:

> But I've captured a few other interesting things in the syslog.
> After doing a
> $ hdparm -c1 -u1 -d1 -X69 /dev/hda
> I saw this in my syslog:
>
> Aug 7 00:32:05 lfs kernel: blk: queue c049195c, I/O limit 4095Mb (mask 0xffffffff)
> Aug 7 00:32:05 lfs kernel: hda: Speed warnings UDMA 3/4/5 is not functional.
>
> The onboard IDE controller is a UDMA-100 controller
> and the disks do run in this mode, too.

Please send dmesg and .config.

--
Bartlomiej

2003-08-06 22:54:53

by Andrew Morton

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

Michael Buesch <[email protected]> wrote:
>
> But I've captured a few other interesting things in the syslog.
> After doing a
> $ hdparm -c1 -u1 -d1 -X69 /dev/hda
> I saw this in my syslog:
>
> Aug 7 00:32:05 lfs kernel: blk: queue c049195c, I/O limit 4095Mb (mask 0xffffffff)
> Aug 7 00:32:05 lfs kernel: hda: Speed warnings UDMA 3/4/5 is not functional.
>
> The onboard IDE controller is a UDMA-100 controller
> and the disks do run in this mode, too.

and

> 149 ide_outbsync 11,4615

it does seem that ide has gone bad. Perhaps you can run `hdaprm -X udma2'
or whatever the `-X' argument is to force it into UDMA2 mode.

But the driver should have done that for itself.

2003-08-06 23:11:59

by Michael Buesch

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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On Thursday 07 August 2003 00:56, Andrew Morton wrote:
> it does seem that ide has gone bad. Perhaps you can run `hdaprm -X udma2'
> or whatever the `-X' argument is to force it into UDMA2 mode.
>
> But the driver should have done that for itself.

I've done -X udma2 and it did a _massive_ performance drop.

root@lfs:/home/mb> hdparm -Tt /dev/hda

/dev/hda:
Timing buffer-cache reads: 128 MB in 0.31 seconds =417.00 MB/sec
Timing buffered disk reads: 64 MB in 3.24 seconds = 19.73 MB/sec

"Timing buffered disk reads" is only as half as fast as without udma2.

I've made a new profile with udma2 enabled and appended it.

The system-performance while dd is way better now, but still not as
good as in 2.4
But for what price? Now I have a disk-speed like DMA-33. :) (on a
DMA-100 controller)

- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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2003-08-06 23:18:55

by Michael Buesch

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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On Thursday 07 August 2003 01:01, Bartlomiej Zolnierkiewicz wrote:
> Please send dmesg and .config.

I've attached them to this mail.

Short note: The error messages from hdd come from
my fu.. CD-recorder. There's no harddisk connected,
so I think you may ignore these messages for now.

>
> --
> Bartlomiej

- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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Subject: Re: [2.6] system is very slow during disk access


On Thu, 7 Aug 2003, Michael Buesch wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> On Thursday 07 August 2003 01:01, Bartlomiej Zolnierkiewicz wrote:
> > Please send dmesg and .config.
>
> I've attached them to this mail.

After removing CONFIG_IDEDMA_IVB=y from your config
"Speed warnings" should go away.

--
Bartlomiej

2003-08-07 04:11:17

by Nuno Silva

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

Hi!

There are some references to: hdparm -a 512 /dev/hda.
For some folks this improves fs performance.

Does it work for you?

Regards,
Nuno Silva

Michael Buesch wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> On Wednesday 06 August 2003 22:31, insecure wrote:
>
>>hdparm -T -t output? dmesg? lspci? /proc/ide stuff?
>
>
>
> root@lfs:/home/mb> hdparm -T -t /dev/hda
>
> /dev/hda:
> Timing buffer-cache reads: 128 MB in 0.37 seconds =343.22 MB/sec
> Timing buffered disk reads: 64 MB in 1.53 seconds = 41.81 MB/sec
>
>
> dmesg doesn't show any unusual messages.
>
>
> root@lfs:/home/mb> lspci
> 00:00.0 Host bridge: Intel Corp. 82845 845 (Brookdale) Chipset Host Bridge (rev 04)
> 00:01.0 PCI bridge: Intel Corp. 82845 845 (Brookdale) Chipset AGP Bridge (rev 04)
> 00:1e.0 PCI bridge: Intel Corp. 82801BA/CA/DB PCI Bridge (rev 05)
> 00:1f.0 ISA bridge: Intel Corp. 82801BA ISA Bridge (LPC) (rev 05)
> 00:1f.1 IDE interface: Intel Corp. 82801BA IDE U100 (rev 05)
> 00:1f.2 USB Controller: Intel Corp. 82801BA/BAM USB (Hub #1) (rev 05)
> 00:1f.3 SMBus: Intel Corp. 82801BA/BAM SMBus (rev 05)
> 00:1f.4 USB Controller: Intel Corp. 82801BA/BAM USB (Hub #2) (rev 05)
> 01:00.0 VGA compatible controller: nVidia Corporation NV25 [GeForce4 Ti4400] (rev a2)
> 03:02.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11)
> 03:02.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11)
> 03:03.0 Multimedia audio controller: Ensoniq 5880 AudioPCI (rev 02)
> 03:04.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8029(AS)
> 03:0c.0 USB Controller: NEC Corporation USB (rev 41)
> 03:0c.1 USB Controller: NEC Corporation USB (rev 41)
> 03:0c.2 USB Controller: NEC Corporation USB 2.0 (rev 02)
>
> root@lfs:/home/mb> cat /proc/ide/drivers
> ide-cdrom version 4.59-ac1
> ide-disk version 1.18
>
> root@lfs:/home/mb> cat /proc/ide/hda/settings
> name value min max mode
> - ---- ----- --- --- ----
> acoustic 0 0 254 rw
> address 0 0 2 rw
> bios_cyl 79780 0 65535 rw
> bios_head 16 0 255 rw
> bios_sect 63 0 63 rw
> bswap 0 0 1 r
> current_speed 69 0 70 rw
> failures 0 0 65535 rw
> init_speed 69 0 70 rw
> io_32bit 1 0 3 rw
> keepsettings 0 0 1 rw
> lun 0 0 7 rw
> max_failures 1 0 65535 rw
> multcount 16 0 16 rw
> nice1 1 0 1 rw
> nowerr 0 0 1 rw
> number 0 0 3 rw
> pio_mode write-only 0 255 w
> slow 0 0 1 rw
> unmaskirq 0 0 1 rw
> using_dma 1 0 1 rw
> wcache 0 0 1 rw
>
>
> root@lfs:/home/mb> cat /proc/ide/hda/model
> IC35L040AVVA07-0
>
>
>
>>--
>>insecure
>
>
> - --
> Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
> Penguin on this machine: Linux 2.6.0-test2 - i386
>
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>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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> Please read the FAQ at http://www.tux.org/lkml/
>

2003-08-07 05:44:26

by Jean-Yves LENHOF

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

> I have massive problems with linux-2.6.0-test2.
> When some process writes something to disk, it's very hard
> to go on working with the system.
>
>
> Some test-szenario:
> $ dd if=/dev/zero of=./test.file
>
>
> While dd is running, xmms skips playing every now and then
> and the mouse is near to be unusable. The Mouse-cursor
> behaves some kind of very lazy and some times it jumps
> from one point on the display to another.
> When I stop disk-access, it works again quite fine.
>
>
> Would be cool, if you could give me some point to start
> for tracking this down.

Maybe this is this one again...

http://www.ussg.iu.edu/hypermail/linux/kernel/0307.1/2552.html

Regards,

Jean-Yves

2003-08-07 09:53:54

by Michael Buesch

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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On Thursday 07 August 2003 06:13, Nuno Silva wrote:
> Hi!

Hi,

> There are some references to: hdparm -a 512 /dev/hda.
> For some folks this improves fs performance.
>
> Does it work for you?

Changing read-ahead doesn't work. Neither to 8 nor to 512.
I think it doesn't have something to do with read-ahead,
because the system-performance-drop occurs while
writing to the disk.
My dd-example wrote to disk:

dd if=/dev/zero of=./t.test


I just ran a few other tests:

dd if=/dev/hda of=/dev/null
doesn't drop system performance and the system is very usable
while dd is running.
So reading from a plain partition is OK.


dd if=/dev/zero of=/dev/hdc7
This slows down the system _very_ much, but it's still usable.
The mouse curser doesn't jump randomly over the screen, like it
did while
dd if=/dev/zero of=./t.test

So my guess, it may have something to do with reiserFS.
So I ran another test:

I did
mke2fs /dev/hdc7
mount /dev/hdc7 /mnt/data_1
cd /mnt/data_1
dd if=/dev/zero of=./t.test

And now the surprise. :)
Here the system-behaviour is exactly the same, as while
writing to the plain partition.
The cursor is not smooth, but it's usable and it doesn't
jump ramdonly over the screen.

So I think it has something to do with reiserFS.
Where can I start to track it down, why reiserFS
is doing this?
Hmm, I'll try to enable
CONFIG_REISERFS_CHECK
and
CONFIG_REISERFS_PROC_INFO

Can somebody tell me how to debug reiserFS with these
options enabled?

> Regards,
> Nuno Silva

Short note: hda and hdc are both exactly the same devices.

- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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2003-08-07 11:05:16

by Michael Buesch

[permalink] [raw]
Subject: Re: [2.6] system is very slow during disk access

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On Thursday 07 August 2003 01:30, Bartlomiej Zolnierkiewicz wrote:
> After removing CONFIG_IDEDMA_IVB=y from your config
> "Speed warnings" should go away.


Aug 7 12:08:35 lfs kernel: blk: queue c04a795c, I/O limit 4095Mb (mask 0xffffffff)
Aug 7 12:08:35 lfs kernel: hdb: Speed warnings UDMA 3/4/5 is not functional.
Aug 7 12:08:35 lfs kernel: blk: queue c04a82ac, I/O limit 4095Mb (mask 0xffffffff)
Aug 7 12:08:35 lfs kernel: ide1: Speed warnings UDMA 3/4/5 is not functional.
Aug 7 12:08:35 lfs kernel: hdd: Speed warnings UDMA 3/4/5 is not functional.

Speed-warning from hda disappeared, but ide1 is still there.
(hdb and hdd are no disks. They are CD-drives, so that's no problem, yet)

>
> --
> Bartlomiej

- --
Regards Michael Buesch [ http://www.8ung.at/tuxsoft ]
Penguin on this machine: Linux 2.6.0-test2 - i386

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