all three IO Schedulers turned on in 2.6.10-rc3-mm1 ???

all three IO Schedulers turned on in 2.6.10-rc3-mm1 ???

[Steven A. DuChene]

I downloaded and built the 2.6.10-rc3-mm1 kernel and I noticed while
configuring it that in the Device Drivers > Block devices > IO Schedulers
area that by default all three IO Schedulers are turned on. Is this a
normal condition or is there only supposed to be one of these turned on?

The reason I am concerned about this is that ever since I have booted
into this kernel I have a lot of things failing and when they fail
they return a message like "Inappropriate ioctl for device"

I get this when trying to do a simple wget (remote address fails to resolve)
and when trying to run any X program against the Xserver running on the system.
-- 
Steven A. DuChene	linux-clusters . AT . mindspring . DOT . com

Re: all three IO Schedulers turned on in 2.6.10-rc3-mm1 ???

[Peter Zijlstra]

On Thu, 2004-12-16 at 14:10 -0500, Steven A. DuChene wrote:
> I downloaded and built the 2.6.10-rc3-mm1 kernel and I noticed while
> configuring it that in the Device Drivers > Block devices > IO Schedulers
> area that by default all three IO Schedulers are turned on. Is this a
> normal condition or is there only supposed to be one of these turned on?
> 
yes, you can change them runtime in /sys/block/<dev>/queue/scheduler

> The reason I am concerned about this is that ever since I have booted
> into this kernel I have a lot of things failing and when they fail
> they return a message like "Inappropriate ioctl for device"
> 
see:
	http://lkml.org/lkml/2004/12/13/69

> I get this when trying to do a simple wget (remote address fails to resolve)
> and when trying to run any X program against the Xserver running on the system.
-- 
Peter Zijlstra <a.p.zijlstra@chello.nl>

Re: all three IO Schedulers turned on in 2.6.10-rc3-mm1 ???

[Jens Axboe]

On Thu, Dec 16 2004, Steven A. DuChene wrote:
> I downloaded and built the 2.6.10-rc3-mm1 kernel and I noticed while
> configuring it that in the Device Drivers > Block devices > IO Schedulers
> area that by default all three IO Schedulers are turned on. Is this a
> normal condition or is there only supposed to be one of these turned on?

They all default to on. There's actually a fourth that is also on, but
you cannot turn that off (noop). It's there if you disable the other
three, in lack of a better way to express that in Kconfig.

> The reason I am concerned about this is that ever since I have booted
> into this kernel I have a lot of things failing and when they fail
> they return a message like "Inappropriate ioctl for device"

The io schedulers don't provide any ioctls, must be something else. I
suggest you strace whatever program is throwing these errors and find
out what is going wrong.

-- 
Jens Axboe