Dtrace port status

[John Birrell]

On Wed, Sep 19, 2007 at 11:34:19PM +0200, Olivier Warin wrote:
> I recently wanted to give dtrace on FreeBSD a try but found this  
> project to be stopped due to a licensing issue.
> Will we see dtrace in the base just like zfs anytime (hopefully) soon ?

I'm am currently trying to find a way around the licensing issues.
Sun is no help at all. The patent clauses in their CDDL are a big deal.
They claim that they don't want to sue anyone over patents, but
when push comes to shove they actually will. Refer to the Netapp
lawsuits.

ZFS is completely contained within optional kernel modules which
do not affect the BSD license status of the kernel.

DTrace consists mainly of kernel modules, however in order for DTrace
to inspect the kernel internals it has to have some code inside
existing BSD licensed files.

An example of the problem is the extra fields that are required in
struct thread. DTrace has a bunch of it's own stuff in there.
I can't just add to proc.h because the only documentation that I
have that indicates that those fields are even needed is in the
CDDL source that is smattered throughout OpenSolaris.

So I have to extend struct thread in an opaque way like the
scheduler appends it's structure.

Long story short.... yes DTrace will be back at some time, but
there isn't a set time line.

--
John Birrell