non-pae kernel??

Hello,

I am using OperSUSE 11.2 and have a early model Dell D400 - and as discussed in this thread I cannot use a PAE-enabled kernel.

But the issue is that ALL of the kernels seem to be PAE enabled. Even though I know the reason why, I would still expect the name to say -pae at the end, like I’m certain they did for 11.0 - so we had kernel-rt, and kernel-rtpae to make the distinction. I’m truly wishing that was the case now.

I need a real-time kernel with PAE disabled - does anyone know a repository where there is one?

Many thanks.

Have you tried

kernel-default

Well, it doesn’t really solve my problem of needing a real-time kernel… although maybe I could patch it - I will investigate this… do you have any suggestions where to start?

You could try compile one from source? If you use the source-rt package you don’t need to patch it (the source) either. I don’t think you can have a real-time capable kernel by just patching the running one, I think you have to recompile/build a new one. But I may be wrong.

system_configuration [LinuxMusicians Wiki]
If you scroll down the site there are some links to howtos for rt-kernel compiling.

On 2010-12-14 03:06, epicurious wrote:
>
> caf4926;2265353 Wrote:
>> Have you tried
>>
>> kernel-default
>
> Well, it doesn’t really solve my problem of needing a real-time
> kernel… although maybe I could patch it - I will investigate this…
> do you have any suggestions where to start?

I understand that all suse kenrels have the exact same source, what it
changes is the configurations (for compilation). So, you have to install
the sources, get the config files of a non-pae kernel and a rt kernel, an
apply to one the configs of the other that you need.

Plus, if you think that there is a justifiable need for a rt, non-pae
kernel, you could ask the devs/packagers to provide it for next versions.


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” at Telcontar)

You are right - and I know how to do this. But I was trying to avoid this scenario. I have been trying to compile a kernel on both laptop and desktop but have had no luck [keep running out of space, “bad magic” errors, etc.]

That is a good idea - it would extend the use of openSUSE for older chip-sets and reconditioned units like my laptop *

Also, I am certain that enabling PAE by default is a newer thing… as I said, before a realtime kernel with PAE was called kernel-rtpae.*

On 2010-12-14 05:06, epicurious wrote:
>
> You are right - and I know how to do this. But I was trying to avoid
> this scenario. I have been trying to compile a kernel on both laptop and
> desktop but have had no luck [keep running out of space, “bad magic”
> errors, etc.]

Compiling a kernel is easy (I can guide you a bit with that), but you need
ample disk space. It is possible to do it in a modest computer, but it will
take a long time, several hours.


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” at Telcontar)

It’s done! I knew how to do it… but the space I had wasn’t quite enough to make an rpm. So I had to make make make :wink: - but thanks for all the offers of help.

On 2010-12-14 09:06, epicurious wrote:

> It’s done! I knew how to do it… but the space I had wasn’t quite
> enough to make an rpm. So I had to make make make :wink: - but thanks for
> all the offers of help.

Good! Hope it works well. :slight_smile:


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” at Telcontar)

On 12/14/2010 06:20 AM, Carlos E. R. wrote:
> On 2010-12-14 09:06, epicurious wrote:
>
>> It’s done! I knew how to do it… but the space I had wasn’t quite
>> enough to make an rpm. So I had to make make make :wink: - but thanks for
>> all the offers of help.

I never mess around with making an rpm for installation. Besides saving the
space and the time, installing with make saves the official kernel on the
system, thus you have a backup in case the new kernel does not boot.

On 2010-12-14 21:48, Larry Finger wrote:

> I never mess around with making an rpm for installation. Besides saving the
> space and the time, installing with make saves the official kernel on the
> system, thus you have a backup in case the new kernel does not boot.

Installing the rpm can do the same, and keeps the package managers
informed. I have never don it that way, but I’m aware of the advantages :slight_smile:


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” at Telcontar)

Hello Carlos!

I understand that all suse kenrels have the exact same source, what it
changes is the configurations (for compilation). So, you have to install
the sources, get the config files of a non-pae kernel and a rt kernel, an
apply to one the configs of the other that you need.

This isn’t quite accurate. As far as I know, the kernel-source-rt does include the rt patch which the kernel source doesn’t. Hence, compiling a kernel from the plain kernel-source will not give you the possibility to apply complete preemption.

The above applies to the sources in the official repositories. You may of course patch the official kernel-source to include the rt patch.

Nice to hear you found a solution though epicurious!

Cheers,
Olav

Thank you all!

Previously, I made rpms so I could install the same kernel on different systems. It’s partly my fault, since I’d last “tweaked” the kernel and unwittingly switched off CONFIG_HIGHMEM so when I actually did what I told myself to do two years ago and bought more RAM - 2GB - my system wasn’t using it all.

So I was hoping that I could just download a new realtime kernel, without having to wait - as I had a show in two days’ time! But now only the default kernel comes with PAE disabled, which I think is unfortunate - if you’re going to have PAE enabled then the naming should have -pae, just as if you have a realtime version, the kernel has -rt.

Anyway, I ended up using a modified version of ketchup to download the kernel appropriate to the most recent realtime patch and put it all together. This worked really well.

Cheers!

On 2010-12-15 02:06, F Sauce wrote:

>> This isn’t quite accurate. As far as I know, the kernel-source-rt does
>> include the rt patch which the kernel source doesn’t. Hence, compiling a
>> kernel from the plain kernel-source will not give you the possibility to
>> apply complete preemption.

I see. Yes, you are right, there is a kernel-source-rt package. Well, the
user would have to install those sources, do the make cloneconfig, then
manually apply the changes of the non-pae kernel, and compile.

On 2010-12-15 08:36, epicurious wrote:

> So I was hoping that I could just download a new realtime kernel,
> without having to wait - as I had a show in two days’ time! But now only
> the default kernel comes with PAE disabled, which I think is unfortunate
> - if you’re going to have PAE enabled then the naming should have
> --pae-, just as if you have a realtime version, the kernel has --rt-.

But you still haven’t explained why you can’t use PAE. :-?


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” at Telcontar)

On 12/15/2010 06:50 AM, Carlos E. R. wrote:
> On 2010-12-15 02:06, F Sauce wrote:
>
>>> This isn’t quite accurate. As far as I know, the kernel-source-rt does
>>> include the rt patch which the kernel source doesn’t. Hence, compiling a
>>> kernel from the plain kernel-source will not give you the possibility to
>>> apply complete preemption.
>
> I see. Yes, you are right, there is a kernel-source-rt package. Well, the
> user would have to install those sources, do the make cloneconfig, then
> manually apply the changes of the non-pae kernel, and compile.
>
>
> On 2010-12-15 08:36, epicurious wrote:
>
>> So I was hoping that I could just download a new realtime kernel,
>> without having to wait - as I had a show in two days’ time! But now only
>> the default kernel comes with PAE disabled, which I think is unfortunate
>> - if you’re going to have PAE enabled then the naming should have
>> --pae-, just as if you have a realtime version, the kernel has --rt-.
>
> But you still haven’t explained why you can’t use PAE. :-?

If you really need an rt kernel, then you will always need to install it
yourself, as I doubt that an official openSUSE distribution will include it. The
changes are inappropriate for most users.

I too want to see why you need an rt kernel.

On 2010-12-15 17:06, Larry Finger wrote:

> If you really need an rt kernel, then you will always need to install it
> yourself, as I doubt that an official openSUSE distribution will include it.

But openSUSE does include it.


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” at Telcontar)

I would not think that the pae would had much latency unless there is really more then 3 gig of memory.

How old is the hardware?

I did - it’s in the thread I linked to in the original post. The Dell Latitude D400 I have has a older Pentium M and it cannot use PAE.

Ah - I think you misunderstand. I was looking for an realtime kernel in a repository that had PAE disabled. I wasn’t looking for a distribution with one [although they do exist - but I don’t like any of them]. I’ve been using Linux for seven/eight years for my work - I’m a musician.

As far as I am aware, PAE doesn’t really affect the latency of a system - just the amount of memory a system can use. Is that correct?

The laptop is an old model Dell D400 - the Pentium M chip doesn’t support PAE.