Re: per-cpu statistics (Re: CVS commit: src)

[Simon Burge <simonb%NetBSD.org@localhost>]

Jason Thorpe wrote:

> On Apr 10, 2008, at 8:59 PM, YAMAMOTO Takashi wrote:
> 
> > while converting existing sysctls is fine, we need to introduce a
> > kernel-userland interface for currently kmem-based statistics
> > (including evcnt) at some point.  i'd like to see something like
> > solaris kstat rather than sprinkling random nodes in the sysctl tree.
> 
> That's certainly fine with me.

I've got a simple proof-of-concept sysctl for fetching evcnts, which is
really the all-or-nothing approach.

I've just start looking at the Solaris kstat interface.  Is there really
much of a difference between a sysctl node and a named kstat?  My
first thought after a bit of reading is that we could add an interface
to query evcnts by name, but then we're just back at sysctl nodes.
At which stage, do we just do away with evcnts and use sysctl nodes
anyways?

I'll keep reading up on kstat, but can someone easily summarise what
kstat gives us over sysctl?

Cheers,
Simon.