Re: [patch] remove the BKL (Big Kernel Lock), this time for real

From: hui
Date: Thu Sep 16 2004 - 18:08:33 EST


On Thu, Sep 16, 2004 at 03:54:12PM -0700, David S. Miller wrote:
> On Thu, 16 Sep 2004 15:51:02 -0700
> Bill Huey (hui) <bhuey@xxxxxxxx> wrote:
>
> > Judging from how the Linux code is done and the numbers I get from
> > Bill Irwin in casual conversation, the Linux SMP approach is clearly
> > the right track at this time with it's hand honed per-CPU awareness of
> > things. The only serious problem that spinlocks have as they aren't
> > preemptable, which is what Ingo is trying to fix.
>
> This is what Linus proclaimed 6 or 7 years ago when people were
> trying to convince us to do things like Solaris and other big
> Unixes at the time.

FreeBSD's SMPng project is stalled for the most part and developers that
disagree with that approach have move onto the DragonFly BSD community.
It has a much more top-down driven locking system that's conceptually
CPU local called tokens, effectively deadlock free and difficult to misused.
It's already been able to multi-thread the networking stack using lock-less
techniques, while the FreeBSD-current tree had to retract their "all or
nothing" approach with threading their network stack. Jeffery Hsu is
the main developer pushing that subsystem.

bill

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/