2004-09-16 12:30:26

by Maciej Soltysiak

[permalink] [raw]
Subject: [2.6.8.1-ck7-web100] Badness in cfq_sort_rr_list

Hi,

I have just had this:
Badness in cfq_sort_rr_list at drivers/block/cfq-iosched.c:428

[ more of the trace at http://dns.toxicfilms.tv/cfq.txt ]

On a 2.6.8.1 with:
- patch-2.6.8.1-ck7.bz2
- web100-2.5.0-200408311033.tar.gz

I know ck7 uses CFQ as deafult and that web100 touches only tcp stuff.

My .config is here:
http://dns.toxicfilms.tv/config.txt

--
Regards,
Maciej



2004-09-16 13:02:46

by Jens Axboe

[permalink] [raw]
Subject: Re: [2.6.8.1-ck7-web100] Badness in cfq_sort_rr_list

On Thu, Sep 16 2004, Maciej Soltysiak wrote:
> Hi,
>
> I have just had this:
> Badness in cfq_sort_rr_list at drivers/block/cfq-iosched.c:428
>
> [ more of the trace at http://dns.toxicfilms.tv/cfq.txt ]
>
> On a 2.6.8.1 with:
> - patch-2.6.8.1-ck7.bz2
> - web100-2.5.0-200408311033.tar.gz
>
> I know ck7 uses CFQ as deafult and that web100 touches only tcp stuff.

You can ignore it, it's harmless. Con has the extra updates to fix this,
they are also in 2.6.9-rc2-mm1 as posted by Andrew earlier today.

--
Jens Axboe

2004-09-16 13:11:19

by Con Kolivas

[permalink] [raw]
Subject: Re: [2.6.8.1-ck7-web100] Badness in cfq_sort_rr_list

Jens Axboe wrote:
> On Thu, Sep 16 2004, Maciej Soltysiak wrote:
>
>>Hi,
>>
>>I have just had this:
>>Badness in cfq_sort_rr_list at drivers/block/cfq-iosched.c:428
>>
>>[ more of the trace at http://dns.toxicfilms.tv/cfq.txt ]
>>
>>On a 2.6.8.1 with:
>>- patch-2.6.8.1-ck7.bz2
>>- web100-2.5.0-200408311033.tar.gz
>>
>>I know ck7 uses CFQ as deafult and that web100 touches only tcp stuff.
>
>
> You can ignore it, it's harmless. Con has the extra updates to fix this,
> they are also in 2.6.9-rc2-mm1 as posted by Andrew earlier today.

The fix for this one has been up for a while here:

http://ck.kolivas.org/patches/2.6/2.6.8.1/2.6.8.1-ckdev/cfq_v2_20040909.patch

Cheers,
Con

2004-09-16 14:51:24

by Maciej Soltysiak

[permalink] [raw]
Subject: Re[2]: [2.6.8.1-ck7-web100] Badness in cfq_sort_rr_list

> You can ignore it, it's harmless. Con has the extra updates to fix this,
> they are also in 2.6.9-rc2-mm1 as posted by Andrew earlier today.
Harmless you say... :-) The machine almost hardlocked. I could only
type my username during login and that's all.
Maybe it is unrelated but I will try the suggested patch.

Thanks,
Maciej


2004-09-16 14:58:06

by William Lee Irwin III

[permalink] [raw]
Subject: Re: [2.6.8.1-ck7-web100] Badness in cfq_sort_rr_list

At some point in the past, Jens Axboe wrote:
>> You can ignore it, it's harmless. Con has the extra updates to fix this,
>> they are also in 2.6.9-rc2-mm1 as posted by Andrew earlier today.

On Thu, Sep 16, 2004 at 04:50:42PM +0200, Maciej Soltysiak wrote:
> Harmless you say... :-) The machine almost hardlocked. I could only
> type my username during login and that's all.
> Maybe it is unrelated but I will try the suggested patch.

Please use technical terms. "almost hardlocked" is ambiguous at best.


-- wli

2004-09-16 15:22:03

by Maciej Soltysiak

[permalink] [raw]
Subject: Re[2]: [2.6.8.1-ck7-web100] Badness in cfq_sort_rr_list

>> Harmless you say... :-) The machine almost hardlocked. I could only
>> type my username during login and that's all.
>> Maybe it is unrelated but I will try the suggested patch.

> Please use technical terms. "almost hardlocked" is ambiguous at best.
1. While being logged in with SSH, I typed date to see the today's
date. Nothing showed up, I tried ctrl+c to break whatever might be
there to break. I tried ctrl+z to try to push the task to background.
No reponse was there.
So I tried logging once more with SSH to my account. I logged in, saw
the MOTD. Once I typed one command - ls for instance - I had the same as above.
So I was able to login with SSH.

2. When I went to the console, I saw the cfq traces. I switched to the
other tty (alt+f2) and tried to log in as root, After typing root and
pressing enter I could not log in this way as with ssh.

3. I tried alt+prn+S to sync. No effects besides the disks sync'd.
So I unmounted them (alt+prn+U) and rebooted (alt+prn+B) and
sent the traces I saw.

Anyway that does not give any clues as to the source of it. Or does
it?

--
Regards,
Maciej


2004-09-16 15:22:00

by Jens Axboe

[permalink] [raw]
Subject: Re: [2.6.8.1-ck7-web100] Badness in cfq_sort_rr_list


(don't trim cc lists... people don't have time to watch linux-kernel all
day)

On Thu, Sep 16 2004, Maciej Soltysiak wrote:
> > You can ignore it, it's harmless. Con has the extra updates to fix this,
> > they are also in 2.6.9-rc2-mm1 as posted by Andrew earlier today.
> Harmless you say... :-) The machine almost hardlocked. I could only
> type my username during login and that's all.
> Maybe it is unrelated but I will try the suggested patch.

Probably unrelated. It can cause some starvation, that should be the
worst effect.

--
Jens Axboe