concurrent sysctl implementation

[Lars Engels]

On Fri, May 08, 2009 at 11:41:17PM +0200, Ed Schouten wrote:
> Hi,
> 
> * vasanth raonaik <vasanth.raonaik at gmail.com> wrote:
> > Hello Jt,
> > 
> > I am a newbee in this alias. I am having a very basic question. It would be
> > really good if you could give me some of this information.
> > Could you please elaborate on what is the current architecture of sysctl
> > implementation and How the concurrency would benefit us.
> 
> Right now sysctl is synchronized using the sysctl lock. The problem is
> that certain sysctls just block for a very long time (especially some of
> the GEOM ones). We also call sysctl when we execute new processes, to
> obtain a random number for the stack protector. This means we have quite
> a lot of contention on it. This lock needs to be there, because sysctls
> can be added and removed on demand.

Why is sysctl used to get a random number? Can't we get a different
source for it?
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 195 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-hackers/attachments/20090509/3f2427f5/attachment.pgp