AIX Kernel

AIX Kernel

Post by paul m hai » Wed, 14 Jun 2000 04:00:00



Quick Question:

What kind of Kernel is the AIX kernel, modular or monolithic?  Are
there any references regarding?

Thanks!

Paul

 
 
 

AIX Kernel

Post by Gary R. Hoo » Wed, 14 Jun 2000 04:00:00



> Quick Question:

> What kind of Kernel is the AIX kernel, modular or monolithic?  Are
> there any references regarding?

Moduler.  Dynamically extensible.  Can have extensions/device drivers
added/removed on the fly.

--
Gary R. Hook / AIX Kernel Development, IBM / These opinions are _MINE_
________________________________________________________________________
A piece of canvas is only the beginning
It takes on character with every loving stroke
This thing of beauty is the passion of an artist's heart
By God's design, we are a skin kaleidoscope    "Colored people", dc Talk

 
 
 

AIX Kernel

Post by Christian Groov » Thu, 15 Jun 2000 04:00:00


Hy



> > Quick Question:

> > What kind of Kernel is the AIX kernel, modular or monolithic?  Are
> > there any references regarding?

> Moduler.  Dynamically extensible.  Can have extensions/device drivers
> added/removed on the fly.

you are right. But as far as i know AIX, it makes rare use of it (in
comparison to LINIX). On
AIX 4.1.x there exists  only some network device drivers and at least IBM's
XTI implementation,
or did this changed ?
LINUX uses modules during installation, to get rid of a * kernel
recompilation. Most distributuions
come with a minimalistic kernel and check out out your hardware
configuration during installation.
Then, they establish a RAM-disk image containing all needed device drivers
at boot time. Both,
the unchanged kernel image and the ram-disk is loaded by the boot-loader. As
a consequence of
this, any distributors may ship its CD-ROM with minimalistic kernel -
package and a rich package
containing device drivers, filesystems and other things. The kernel
customisation is done by installing
without any recompilation. I do not believe, that AIX is comparalbe flexible
like this !!

Anyway, AIX, LINUX and other UNIX systems have a monolythic design. The
modular concept
is only an additional feature, that allows to load drivers and other
components dynamically on demmand
into the kernel. That may saves ressources and provides a more simple test
of newly developped
device drivers.
You may also find message passing kernels like HURD, Digital-UNIX ( Mach3 )
or the ole
NextStep or NT. Some guy's feel e*d  knowing that their OS sends
messages, to carry out their
tasks. These concepts are (mostly) slower and need more ressources, since
most CPU's need more
instructions to handle a message queue.  Passing a kernel request via
soft-interrupt or other calling
methodes is faster.

Think pragmatically, use monolithic kernels !!!

Groovie

 
 
 

AIX Kernel

Post by Dave Marquard » Thu, 15 Jun 2000 04:00:00





> > > Quick Question:

> > > What kind of Kernel is the AIX kernel, modular or monolithic?  Are
> > > there any references regarding?

> > Moduler.  Dynamically extensible.  Can have extensions/device drivers
> > added/removed on the fly.

> you are right. But as far as i know AIX, it makes rare use of it (in
> comparison to LINIX). On
> AIX 4.1.x there exists  only some network device drivers and at least IBM's
> XTI implementation,
> or did this changed ?

Actually, most device drivers are kernel extensions.  Very few, if
any, are part of the kernel itself.

-Dave

 
 
 

AIX Kernel

Post by Norman Levi » Thu, 15 Jun 2000 04:00:00



> Hy



> > > Quick Question:

> > > What kind of Kernel is the AIX kernel, modular or monolithic?  Are
> > > there any references regarding?

> > Moduler.  Dynamically extensible.  Can have extensions/device drivers
> > added/removed on the fly.

> you are right. But as far as i know AIX, it makes rare use of it (in
> comparison to LINIX). On
> AIX 4.1.x there exists  only some network device drivers and at least IBM's
> XTI implementation,
> or did this changed ?
> LINUX uses modules during installation, to get rid of a * kernel
> recompilation. Most distributuions
> come with a minimalistic kernel and check out out your hardware
> configuration during installation.
> Then, they establish a RAM-disk image containing all needed device drivers
> at boot time. Both,
> the unchanged kernel image and the ram-disk is loaded by the boot-loader. As
> a consequence of
> this, any distributors may ship its CD-ROM with minimalistic kernel -
> package and a rich package
> containing device drivers, filesystems and other things. The kernel
> customisation is done by installing
> without any recompilation. I do not believe, that AIX is comparalbe flexible
> like this !!

> Anyway, AIX, LINUX and other UNIX systems have a monolythic design. The
> modular concept
> is only an additional feature, that allows to load drivers and other
> components dynamically on demmand
> into the kernel. That may saves ressources and provides a more simple test
> of newly developped
> device drivers.
> You may also find message passing kernels like HURD, Digital-UNIX ( Mach3 )
> or the ole
> NextStep or NT. Some guy's feel e*d  knowing that their OS sends
> messages, to carry out their
> tasks. These concepts are (mostly) slower and need more ressources, since
> most CPU's need more
> instructions to handle a message queue.  Passing a kernel request via
> soft-interrupt or other calling
> methodes is faster.

> Think pragmatically, use monolithic kernels !!!

AIX used loadable modules long before it became the 'in thing' with Linux.
However, the sysadmin does NOT have the choice of what routines are loaded as modules or
kernel processes in AIX and in Linux, you have a great choice.  So, in some ways, Linux
has it over AIX.  On the other hand, because you do NOT have the choice of picking routines -
mainly because you do not have access to the source in AIX - many parameters are externalized
and you don't have to recompile the kernel to change a parameter that AIX might store in the
ODM.  Instead, in Linux you have to recompile - or use work arounds like the "rdev" command
to patch the kernel.   To net it out, both are NOT monolithic kernels.
--
Norman Levin