How to recompile Puppy 4.1 kernel with SMP support?

[liberomureddu]

I added the following:

* Tickless System
* High Resolution Timer
* Symetric mutli-processing (SMP)
* SMP Hyperthreading
* Multi-core scheduler

...

If anyone is interested, let me know![/img]

Hi Nick,
thanks for working on that.
I'm really interested in this, I have just a question: the options you added are good for a audio workstation puppy? I'm not expert at all, I just googled around and saw that "realtime preemption" is considered important for a linux based audio environment.
http://wiki.linuxmusicians.com/doku.php ... ime_kernel
Is this option included in one of those you mentioned above?

[jboettge]

@liberomureddu
(No, I'm not NickBiker

Imho, for any kind of post processing realtime capabilities or not required.
So, if you mix up your own tape you don't need it. Also not for capturing.
You won't experience the delay of about 10ms from your click to the reaction of the system.

But, if you connect any midi device (or playing your sound from the keyboard) it maight be useful for not experiencing the delay.
Or, if you capture in parallel different streams, performing specific automated action for channel a as reaction to the input from channel b. If doing real time processing with your data, e.g. automatically changing filter charateristics due to some specific sound DURING the capture process. Afterwards it doesn't matter because any real program will synchronize your channels.

Real time capabilities just give better chance to respond very fast on events. So, if you don't have to trigger anything very quickly, you won't experience it.
Other words for that: low latency kernel.
Probbably you also increase total overhead of your system (as you do with smp enabled on a single core cpu, too). But not to much, I guess about 2%

Best regards,
Jörg

[liberomureddu]

@ Jörg

thanks for your answer,
I know that I need a low latency while track overdubbing/playing live electronics and not during tracking/mixing (even if, doing a lot of recordings of classical music, quite often I am in the same room with the player, and if I have to check the recording as well as the mistakes of the players, I need to track also with quite low latencies - if I can (not more than 256 samples, usually), in order to not being disturbed by the acoustic sound of the players. and the sound on the headphones). I just never had so much the need to think in terms of kernel in order to achieve low latency (no irony, just musician's mind )

Having sold last year my g4 powerbook, and switched to pc... ehm...windows, I'm checking the possibility of a linux system. Windows xp could be fine, to be honest, but I cannot tolerate, (as a former mac user), that I have to install the system, few patches, the (maybe 10) software I use the most, and keep it safe and untouched: no internet, no trying other software (unless having another partition dedicated to that). etc. etc. In this way, winxp is really stable, just feels a little win95 again.... And somehow, I learnt many things from macosx (command line, basic of compiling, open-source sofware), that I feel much better under Linux, nowadays. I don't want to learn anything about regedit etc, if you know what I mean...

Tried ubuntu since many years (also on my mac), but I don't feel good with it, simply... a little too big. Puppy Linux is the first distribution that makes me feel at home... and it's sooo fast and pleasant to work with.

That said (just to say thanks to the developer and the community), I'm just confused about the different kernel versions and which are good for audio: I read somewhere that recent kernels (as in puppy) don't need the real time patch, other recommend it. And I'm collecting infos around, in order to understand if I have to dive myself into kernel compiling or not. I'll continue to try/explore/ask...

CIao
Libero

[erikson]

(My post of Sun Oct 12)

Results of today:

Using Puppy 4.1-k2.6.25.16 I recompiled the kernel from Barry's source, with Barry's original config. For various reasons it took me a couple of retries "from scratch".

I only did the 'make oldconfig' and 'make' which produced bzImage (with the lzma pet installed it's now 1589 KB i.e. nearly same size as original vmlinuz). I did *not* 'make modules_install' and did *not* update modules in initrd.gz - my reasoning is that these "ought" to be the same since I "self-compiled". I also did not yet recompile aufs.

I copied bzImage, renamed it to vmlinuz and rebooted (with unionfs).

Lo and behold, Puppy boots with the recompiled vmlinuz.

So the next step is to adapt the configuration, to include usb driver support, and see if my goal is achieved (boot full-install off external usb hdd).

Status update, for info.

I adapted the configuration, including the usb drivers as static modules in the kernel, and I compiled successfully. I mean, the recompiled vmlinuz booted frugal Puppies fine.

But with this recompiled kernel I could *not* boot a full install from external usb hdd. Error message: "Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block (0,0)".

Ultimately I implemented it another way, cfr thread How to do a full install on external USB hdd?

[jboettge]

Thanks, Libero, I understand about your situation.
And yes, breaking your windows for all the updates etc. is not that nice.
Due to that it is always a good idea to separate data and system partition and having always a snapshot/ image of your system before doing anything. Nowadays I use an old version of vmware workstation, doing any experiment within a virtual machine. For that I'm so keen on puppy with SMP. Ubuntu is bad in performance if you do that. Even NT4 VM is faster on NT4 host (very strange because it is said emulating the same OS gives poor performance).

I wouldn't suggest to do your real time tasks within a VM but it may worth to do everything else in one ore more. This way your system stays small and clean, and recovering the backup of a VM takes you just the time to copy. So, if having time it may be worth a try.

BTW, I compared vmware workstation 4.5.3 on NT4 server Sp6a with vmware server 1.0.3 on ubuntu desktop 6.06lts. Which may not fully realistic but fine with my hardware. And there was this working howto for ubuntu and vmware

What about your computer system? Single or multi core?

Greetings,
Jörg

[jcoder24]

MU:

Do you still have the System.map created when you compiled this kernel? It seems unleashed uses it.

It would be cool to have newly compiled kernels as an unleashed 'kernel archive', that you can just drop into unleash and rebuild.

[MU]

jcoder,
It should be the one that I attach.

Mark

[liberomureddu]

I wouldn't suggest to do your real time tasks within a VM but it may worth to do everything else in one ore more. This way your system stays small and clean, and recovering the backup of a VM takes you just the time to copy. So, if having time it may be worth a try.

What about your computer system? Single or multi core?

Hi Jörg,
my system is based on a Intel dq35jo motherboard with Intel Core2 Quad Processor Q6600 2.40 GHz and 2Gb of ram.
Then, I have two hds, one for the system, one for the audio files and documents.
In the second hd, I have another partition in which I keep a cloned copy of the win system.
I'll check the vmware, never tried, thanks for the hint, nowadays I tend to test windows stuff under Wine.
What I really like about puppy, is that I can easily launch a clean copy of the system, and/or save many pup save files.
What I'm looking for (and I'm slowly working on it), is to have a personal puppy remastered with all the music software I need. In this way I'd feel safe also in live situation, knowing that I have a copy of the full system in a cd/dvd.
Ciao
Libero

[MU]

I was requested to upload the files again to another mirror.
So here they are:
http://puppyisos.org/files/sfs/Puppy-4.1-smp/

Password:
http://murga-linux.com/puppy/viewtopic.php?t=28930

I hope they all are the correct, last recent versions.
Mark