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Date: Wed, 7 Jul 2004 20:48:45 -0700
From: David Schultz <das@FreeBSD.ORG>
To: Eitarou Kamo <e-kamo@trio.plala.or.jp>
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cc: Daniel Ellard <ellard@eecs.harvard.edu>
Subject: Re: Article on Sun's DTrace
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On Wed, Jul 07, 2004, Eitarou Kamo wrote:
> FreeBSD has good features such as jail, chroot e.t.c. which can controll

Solaris 10 has these features, too, but I'm not sure what that has
to do with DTrace.

> process or resources in parallel. So you need not port DTrace entirely.
> You can implement DTrace like one from scratch. Using legacy system
> sometimes makes new system feature. I would rather expect new one than
> porting. DTrace is one of example, I think. You may be able to fork new 
> debug
> process in parallel in the future. If I dare name it, It's "B(SD)Trace"? 
> But it's up to
> your effort. DTrace is a pioneer work. And for the people like me who 
> bothers
> to put the debug lines in kernel this must be powerful tool.

The page referenced earlier in this thread pointed out that 6
staff-years went into DTrace.  That's accurate, and we're not
talking about part-time employees or people who don't know what
they're doing.  The D compiler aside, this is not a small matter
of programming that can just be ported to a new OS or machine
architecture in a few months.

That said, there is prior work in this area, such as:
http://oss.software.ibm.com/developer/opensource/linux/projects/dprobes/
But these other efforts don't come close to DTrace.