Linked by Eugenia Loli on Fri 3rd Feb 2006 07:45 UTC, submitted by bcantrill
General Development This article goes into the motivation and architecture for DTrace -- and describes some of the problems that remain to be solved in system observability. The article also includes a short case-study on using DTrace to find a real problem -- a problem that was ultimately due to some seriously fugly code in a monitoring app.
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RE[2]: Nice article
by CaptainPinko on Fri 3rd Feb 2006 15:24 UTC in reply to "RE: Nice article"
CaptainPinko
Member since:
2005-07-21

I don't think it'd be possible since it wouldrequire kernel level components and thus would be linked against the kernel ergo needing to be GPL licensed (which it is not) or applied seperately as a software patch.

Reply Parent Score: 1

RE[3]: Nice article
by ecko on Fri 3rd Feb 2006 16:00 in reply to "RE[2]: Nice article"
ecko Member since:
2005-07-08

I'm not a lawyer or anything but it might be possible to just reimplement the kernel layer of DTrace from scratch. I mean it probably just requires certain hooks into the running kernel which already exist for debugging. I'm making this sound trivial and it's really not but legally I think it might be possible. If not there's no reason we can't come up with a work-alike for DTrace.

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RE[4]: Nice article
by JonAnderson on Fri 3rd Feb 2006 16:55 in reply to "RE[3]: Nice article"
JonAnderson Member since:
2005-07-06

You also have to consider patent infringement as well
as copyright infringement.

Reply Parent Score: 1

RE[3]: Nice article
by bcantrill on Fri 3rd Feb 2006 16:59 in reply to "RE[2]: Nice article"
bcantrill Member since:
2005-09-16

I am not a lawyer (and this is not legal advice) but as far as CDDL is concerned, you can drop DTrace into anything. (Yes, Microsoft could drop DTrace into Windows or IBM could drop it into AIX -- were either so inclined.) The issue around Linux is the GPL, not the CDDL: one would have to consult the FSF as to the interoperability of CDDL with the GPL, and Linus as to the Linux definition of the Program. Historically, the FSF has said that CDDL and GPL don't mix -- but Torvalds has been very murky on his definition of the Program. (In particular, the legal status of so-called "Tainted kernels" has never been tested.) If the definition were firmed up to limit the definition of the Program to those components explicitly licensed under the GPL (i.e. a file-based approach), then one could presumably drop DTrace into Linux without violating the GPL. I think if the Linux folks wanted DTrace enough -- and certainly if Linus wanted it -- they could find a way to legally do it. That said, I don't think there's much interest in DTrace among the influential Linux folks...

Reply Parent Score: 1