RE: RT patch acceptance

Zwane Mwaikambo
2005-05-30T16:31:19Z

On Mon, 30 May 2005, kus Kusche Klaus wrote:

> I didn't state that a hard-RT linux is simpler, technically
> (however, personally, I believe that once RT linux is there, *our*
> job of writing RT applications, device drivers, ... will be simpler
> compared to a nanokernel approach).

I can't quite see how, in my experience they involve the same
effort, but i guess that's personal opinion.

> I just stated that for the management, with its limited interest and
> understanding of deep technical details (and, in our case, with bad
> experiences with RT plus non-RT OS solutions), a one-system solution
> *sounds* much simpler, easier to understand, and easier to manage.
>
> Decisions in companies aren't based on purely technical facts,
> sometimes not even on rational arguments...

But decisions for the Linux kernel must always be rational and technical.
Regarding ease of maintenance, debugging/maintaining an application on a
nanokernel (ie isolated) is a lot easier than something as large and
complex as the Linux kernel. This also applies for QA and general
verification.

> And concerning support:
>
> * If we go the "pure linux" way, we may (or may not) get help from
> the community for our problems (it did work quite well up to now),
> or we could buy commercial linux support.

Considering how controlling your management is, i'm surprised you'd stake
your business on something as non deterministic as the Linux kernel
mailing list.

> * If we go the "nanokernel plus guest linux" way, we will not get
> support from the nanokernel company for general linux kernel issues,

I find that hard to believe literally any company which sells you
operating system software will be more than willing to provide you support
for the supplied components, obviously at a price but they are after all
in the business of making money.

> the community help will also be close to zero, because we no
> longer have a pure linux system, and the community is not able to
> reproduce and analyze our problems any longer (in the same way lkml
> is rather unable to help on vendor linux kernels or on tainted
> kernels), and the same holds for most companies offering commercial
> linux support.

A volunteer supported public forum as a means of handling technical issues
for a company doesn't sound like a good idea.

> Hence, w.r.t. support, the nanokernel approach looks much worse.

I can't quite see how you drew that conclusion. The fact is, pay someone
and they'll resolve your problems.

Regards,
Zwane