DTrace on LKML
By bmc on Aug 20, 2004
Yes, you missed something Julien: you forgot to type "dtrace" into google. (If there were a super-nerd equivalent of the Daily Show, we might expect Lewis Black to say that -- probably punctuated with his usual "you moron!") If you had done this, you would have been taken to the DTrace BigAdmin site which contains links to the DTrace USENIX paper, the DTrace documentation, and a boatload of other material that supports the claims in The Register story. In fact, if you had just scrolled to the bottom of that story you would have read the "Bootnotes" section of the story -- which provides plenty of low-level supporting detail. (Indeed, I'm not sure that I've ever seen The Register publish such user-supplied detail to support a story.)> http://www.theregister.co.uk/2004/07/08/dtrace_user_take/: > "Sun sees DTrace as a big advantage for Solaris over other versions of Unix > and Linux." That article is way too hypey. It sounds like one of those strange american commercials you see sometimes at night, where two overenthusiastic persons are telling you how much that strange fruit juice machine has changed their lives, with making them loose 200 pounds in 6 days and improving their performance at beach volleyball a lot due to subneutronic antigravity manipulation. You usually can't watch those commercials for longer than 5 minutes. The same applies to that article, I couldn't even read it completely, it was just too much. And is it just me or did that article really take that long to mentioning what dtrace actually IS? Come on, it's profiling. As presented by that article, it is even more micro optimization than one would think. What with tweaking the disk I/O improvements and all... If my harddisk accesses were a microsecond more immediate or my filesystem giving a quantum more transfer rate, it would be nice, but I certainly wouldn't get enthusiastic and I bet nobody would even notice. Maybe, without that article, I would recognize it as a fine thing (and by "fine" I don't mean "the best thing since sliced bread"), but that piece of text was just too ridiculous to take anything serious. I sure hope that article is meant sarcastically. By the way, did I miss something or is profiling suddenly a new thing again? Regards, Julien
Sometimes the bigotry surrounding Linux suprises even me: in the time he took to record his misconceptions, Julien could have (easily!) figured out that he was completely wrong. But I guess that even this is too much work for someone who is looking to confirm preconceived notions rather than understand new technology...
Fortunately, one of the responses did call Julien on this, if only slightly:
Of course, the responder misses the larger point about DTrace -- that one can instrument one's system arbitrarily and safely with DTrace -- but at least he correctly identifies one capacity in which DTrace clearly leads the pack. And I suppose that this is the best that a rival technology can expect to do, so close to the epicenter of Linux development...\* Julien Oster: > Miles Lane
writes: > >> http://www.theregister.co.uk/2004/07/08/dtrace_user_take/: >> "Sun sees DTrace as a big advantage for Solaris over other versions of Unix >> and Linux." > > That article is way too hypey. Maybe, but DTrace seems to solve one really pressing problem: tracking disk I/O to the processes causing it. Unexplained high I/O utilization is a \*very\* common problem, and there aren't any tools to diagnose it. Most other system resources can be tracked quite easily: disk space, CPU time, committed address space, even network I/O (with tcpdump and netstat -p). But there's no such thing for disk I/O.