[Gluster-users] glusterfs performance issues - meta

[Whit Blauvelt]

On Tue, Jan 08, 2013 at 04:49:30PM +0100, Stephan von Krawczynski wrote:

> > Pointing out that a complex system can go wrong doesn't invalidate complex
> > systems as a class. It's well established in ecological science that more
> > complex natural systems are far more resilient than simple ones. A rich,
> > complex local ecosystem has a higher rate of stability and survival than a
> > simple, poorer one. That's assuming the systems are evolved and have niches
> > well-fitted with organisms - that the complexity is organic, not just
> > random.
> 
> That is a good example for excluded corner cases, just like the current split
> brain discussion. All I need to do to your complex natural system to
> invalidate is to throw a big stone on it. Ask dinosaurs for real life
> experience after that. 

Throw a big enough stone and anything can be totally crushed. The question
is one of resilience when the stone is less than totally crushing. The
ecosystem the big stone was thrown at which included the dinosaurs survived,
because in its complexity it also included little mammals - which themselves
were more complex organisms than the dinosaurs. Not that some simpler
organisms didn't make it through the extinction event too. Plenty did. The
chicken I ate for dinner is a descendant of feathered dinosaurs.

Take two local ecosystems, one more complex than the other. Throw in some
big disturbance, the same size of disruption in each. On average, the
complex local ecosystem is more likely to survive and bounce back, while the
simple one is more likely to go into terminal decline. This is field data,
not mere conjecture. Your argument here could be that technological systems
don't obey the same laws as ecosystems. But work in complexity theory shows
that the right sorts of complexity produce greater stability across a broad
range of systems, not just biological ones. 

Free, open source software's particular advantage is that it advances in a
more evolutionary manner than closed software, since there is evolutionary
pressure from many directions on each part of it, at every scale.
Evolutionary pressure produces complexity, the _right sort_ of complexity.
That's why Linux systems are more complex, and at the same time more stable
and manageable, than Windows systems. 

Simplicity does not have the advantage. Even when smashing things with
rocks, the more complex thing is more likely to survive the assault, if it
has the right sort of complexity.

Best,
Whit