Re: DragonFlyBSD for embededd system...

[Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx>]

:Hello community!
:
:Who compare DragonFlyBSD kernel with QNX kernel?
:Interestin read article about comare DragonFlyBSD kernel with QNX kernel

    Well this sounded interesting so I did a google search and found a 
    number of good comments, but no real articles comparing the abstractions
    used by the two.  It does seem that people 'outside' our developer
    forums really *DO* understand what DragonFly is trying to do, which is
    quite gratifying. 

    I found comments from people describing DragonFly as a Hyrbid-OS (hybrid
    between monolithic and pure messaging), and that is 100% correct.

    I think we have already demonstrated that judicious use of messaging 
    and threads to break up major subsystems results in a HUGELY simplified
    programming model (especially when it comes to concurrency) without 
    necessarily sacrificing performance.  We haven't even *tried* to
    optimize what we've done so far with the network stack, and yet Jeff
    has managed to thread nearly the entire thing with virtually no sacrifice
    in performance vs FreeBSD-4, and the code is like 95% of the way towards
    MP safeness in regards to being able to turn off the BGL for those 
    threads.  Not only that but we have already been able to leverage the
    model in very simple ways to implement things that make a real difference
    with regards to Gigabit performance.

    Our ability to turn off the Big Giant Lock in a major subsytem is going
    to be an important milestone for us, and we are very close now to being
    able to do it in the network subsystem.

					-Matt
					Matthew Dillon 
					<dillon@xxxxxxxxxxxxx>