I was reading a great article on a DTrace knockoffs by Adam Leventhal. Ok, only one is mentioned in the article - Systemtap - but it's a very entertaining read and makes me think there's a fair bit of that green stuff and NIH syndrome, about in the Linux world.
Whilst DTrace is a brilliant bit of technology that is slowly being implemented in various other operating systems, it's the heated debate in the comments that I want to comment on.
Believe it or not, there is not a single comment from the Linux community that says "Fair cop, Systemtap is a very bad attempt at DTrace. We really should be looking at ways of porting DTrace to Linux". Nope, instead there a debate about GPLv2 vs CDDL, caused by an attempt to defend why DTrace hasn't been ported to Linux. The underlying theme from the Linux side is that it's the CDDL license that is stopping DTrace from being ported to Linux.
I'm not a lawyer, and nor have I studied the GPLv2 or CDDL licenses in depth, but think about it for a moment. CDDL licensed code has been incorporated into other proprietary and open source operating systems, each with their own licenses. If CDDL were the one doing the restricting, surely it couldn't be included in these products?
My take is it's actually the GPLv2 that is stopping the porting of DTrace to Linux. It's the GPLv2 that demands that any code linked with GPLv2 code must not be any more restrictive than the GPLv2. It's the GPLv2 code that is incompatible with other more restrictive licenses. NOT CDDL - it's the tolerant one of the two.
I am a fan of BOTH Linux and Solaris, for each of their own merits. What I'm not a fan of is FUD.