What is DF aimed at?

Danial Thom danial_thom at yahoo.com
Mon Jun 5 04:26:32 PDT 2006



--- Dmitri Nikulin <dnikulin at xxxxxxxxx> wrote:

> On 6/5/06, Danial Thom <danial_thom at xxxxxxxxx>
> wrote:
> >
> >
> > --- Matthew Dillon
> <dillon at xxxxxxxxxxxxxxxxxxxx>
> > wrote:
> >
> > > :Uh, how do you get that? Clustering
> implies
> > > :networking, and Matt has repeatedly stated
> > > that
> > > :he doesn't really care about network
> > > performance.
> > > :
> > > :And clustering implies servers, which Matt
> has
> > > :recently and repeatedly stated aren't his
> > > focal
> > > :point. I don't see how you can have one as
> a
> > > goal
> > > :and not the other. Clustering required
> hightly
> > > :efficient networking first and foremost.
> > > :
> > > :DT
> > >
> > >     Er, I said no such thing.  You
> apparently
> > > did not read my
> > >     posting(s) very carefully.
> >
> > You said you only wanted "very good
> networking"
> > and that if you wanted to push traffic at the
> > bleeding edge you should get dedicated
> hardware
> > solutions from cisco.
> >
> > You know optimizing networking isn't such a
> bad
> > thing. You can have your cake and eat it too.
> > Having stellar networking performance will
> not
> > hurt your project, nor is it a "waste of
> time".
> > It would make your OS much more attractive to
> a
> > much wider user base. Even Intel gave in and
> > decided to build a CPU to win the benchmarks.
> > People want the best. No-one is going to
> notice
> > if you're 3rd best, but everyone will notice
> if
> > you're #1.
> 
> People use Linux and it's far from the best in
> security, stability and
> for many cases even performance. They use it
> because it does a lot and
> is marketable. Done. Quality doesn't matter
> otherwise it would never
> have left the garage.
> 
> Even so, optimizing every last possible drop
> from the network stack is
> *not* compatible with the goals of this
> project. For example, if you
> understand the LWKT system and Matt's
> presentation/emails regarding
> the way socket threads are distributed on
> multi-processor systems,
> you'll note that they're split by port and
> bound to that CPU for their
> lifetime. This means that load balancing is not
> as optimal as
> possible, since actual load is not factored in.
> However, work
> aggregation is a lot more successful, because
> migrations are costly.
> Also, the system itself is near lockless and,
> as far as localised
> network stacks go, impressively optimal
> already.
> 
> Since getting proper load balancing of the
> threads in would be counter
> to DragonFly's very architecture, and since
> that optimization itself
> has significant downsides and can actually make
> a pitifully small
> positive difference, there's no point
> optimizing to that extreme. This
> is an example, I'm sure Matt could conjure many
> more cases where the
> extra optimization just isn't worth it, but he
> has better things to
> do.
> 
> I don't know about "stellar" here. Let's wait
> until more of the kernel
> is MPSAFE, including the network stack, and do
> a bench set against a
> few instances of FreeBSD and Linux. I'd be more
> than happy to try it
> out, I've got some em (Intel gigabit) cards and
> an X2 4400+ and that's
> a nice start. You can try it on your millions
> of dollars worth of 10GE
> machines. Contribute to the project! You have
> money and obviously a
> lot of spare time, so help the project out
> instead of insulting its
> developers. That'll be a good deed and you may
> realise just how great
> this community is when you're not perceived as
> an ass bandit.
> 
>   -- Dmitri Nikulin
> 

Why would I contribute to a project that has in 3
days told me:

- they don't care about my goals
- *nix isn't suitable as a network appliance
- it unreasonable for me to not want my console
filled with spammy stray interrupt messages, and
to go fix it myself
- I don't know anything about hardware

I think that one thing I got out of the monowall
article is that you can't choose an OS that
doesn't have as a priority maintaining optimized
network performance. I think he's right about
that. He's wrong about choosing OpenBSD for a lot
of reasons, but I really don't think you're
trying to build a general purpose O/S here,
because you reject many of the commerical uses of
'BSD as being unimportant to you. You can't be
good at something by accident. If there is no
effort to be good at something you probably won't
be good at it. 

DT

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 





More information about the Users mailing list