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Dividing the Linux desktop
LWN.net Weekly Edition for June 13, 2013
A report from pgCon 2013
Little things that matter in language design
Posted Oct 7, 2011 10:02 UTC (Fri) by tialaramex (subscriber, #21167)
This isn't a _huge_ audience, but it is one that's comfortable paying Oracle money. Making sure these people have a reason to ask specifically for Oracle's Linux, not Red Hat, will pay for itself. Previously DTrace was a reason for Solaris administrators to resist going Linux at all, but Oracle doesn't care about that, so it wants DTrace on Linux.
The license doesn't actually matter so much. If you know you want DTrace, that's a reason to choose Oracle, because the DTrace experts work for Oracle.
Posted Oct 7, 2011 20:36 UTC (Fri) by bcantrill (guest, #31087)
Posted Oct 8, 2011 23:53 UTC (Sat) by tialaramex (subscriber, #21167)
Posted Oct 10, 2011 1:43 UTC (Mon) by vonbrand (subscriber, #4458)
Presumably the variables and functions to monitor are sufficiently different between Solaris and Linux that the supposed advantage of dtrace just doesn't exist.
Posted Oct 7, 2011 12:01 UTC (Fri) by fuhchee (subscriber, #40059)
Posted Oct 8, 2011 19:02 UTC (Sat) by rahulsundaram (subscriber, #21946)
Posted Oct 8, 2011 19:30 UTC (Sat) by fuhchee (subscriber, #40059)
I assume you're referring to utrace/uprobes. Yes, only probing general user-space requires these, and we can hardly wait until these are mainstream.
"and everything is in the mainline kernel"
If you're repeating the previous point, ok.
If you're suggesting that a tool must be distributed within the kernel tree in order to be useful, then considerable experience says otherwise.
Posted Oct 8, 2011 19:59 UTC (Sat) by rahulsundaram (subscriber, #21946)
Posted Oct 10, 2011 4:20 UTC (Mon) by cmccabe (guest, #60281)
There's a comparison of the 4 horses in this race at:
It's worth noting that perf isn't really comparable to the other 3 systems because it has a lot more peformance impact. It's really intended more for profiling than for running in production.
Also, LTT-ng and DTrace are not in mainline.
Posted Oct 25, 2011 21:36 UTC (Tue) by oak (guest, #2786)
With LTTng you can profile "everything" happening in the system with pretty low overhead, i.e. when you still aren't sure what exactly is causing the issues. The others are intended for more targeted tracing where you often write your own script to trace things.
On other platforms than x86, one Systemtap issue is that it relies completely on kprobes instruction emulation to be correct. There were a lot of issues in that e.g. on ARM which have been only recently corrected.
Posted Oct 10, 2011 18:18 UTC (Mon) by khc (subscriber, #45209)
A coworker ported our code to Solaris and dtrace hasn't had a problem with it yet. The situation is not ideal as we actually ship on Linux, but we only use tracing internally now so it's not too big of a deal.
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