Kernel Tracing With LTTng On Ubuntu Maverick

francis-giraldeau writes "Linux Tracing Toolkit (LTTng) provides high-performance kernel tracing for Linux. This is the killer app for system level debugging and performance tuning. It's now easier than ever to install, with packages released for Ubuntu Maverick. The short introduction to kernel tracing shows how to interpret a simple kernel trace and relate it to strace. I would like to ask Slashdot readers what they would expect as features for a kernel tracing analysis tool, because I'm starting my PhD on this topic and looking for ideas. Also, I wonder why LTTng is not mainline yet. Will Linus Torvalds see the light in 2011?"

Goal of the PhD work?

[Anonymous Coward]

What is the goal of your work? Do you want to compare kernel tracing solutions and identify critical features in the process of coming up with a reasonable taxonomy? Do you want to implement something? Do you have a specific application for kernel tracing (e.g. informing performance tuning measures in enterprise environments which would probably be of interest to businesses)? Just throwing together a list of desired features is not going to be of interest to anyone, I guess. You have to come up with a motivation for each of the features, argue why this feature is necessary for the application at hand or for any application of kernel tracing in general, cite literature that gives evidence for your assumptions and conclusions. Maybe if you told the people what kind of work you're interested in and what the interest of your advisor(s) is, in which reasearch context (department, university) you are working, they could make sensible suggestions as to which features might be interesting to you.

Re:Crowd-sourcing a degree...

[maxwell demon]

Well, I guess his PhD would not be about imagining those features, but about implementing them. He asked for ideas what to implement, not for ideas how to implement it.

Re:Crowd-sourcing a degree...

[francis-giraldeau]

The reason is that I would like to make my research useful for tracing users, and I think the best way to do it is to ask people what they really need. I will give credits to those how helped my, why not? ;-)

That it is safe to use in a production environment

[Dug]

Not that much point having a tracing tool if an inexperienced admin cannot safely use it on a live system which has a problem.

A problem already solved with DTrace on Solaris http://docs.sun.com/app/docs/doc/817-6223 [dpp]

Ubuntu Only?

[hduff]

Why does the OP mention the Ubuntu package when the project releases a tarball?

There is no need to make news distro-centric when it does not need to be. The submitter should check to see what other binary packages are available or not mention them at all.

See the light?

[codegen]

Maybe I'm reading slashdot too early on a weekend morning, but I find the last statement of the summary particularly offensive. It seems like everyone who has some sort of kernel widget wants a PR campaign to get it included in the mainline. How about you finish your Ph. D. first and provide some convincing evidence as to why every single person running Linux has to have the tool? The trace tools are available as a package for anyone who wants them now. Why should the mainline be burdened with maintaining the package unless a significant number of users need it?

Some googling

[diegocg]

Also, I wonder why LTTng is not mainline yet

Well, a bit of searching [lkml.org] would have answered your question [lttng.org]

The LTTng maintainer has been working for months (years?) to get the kernel tracing into a decent shape. These days the Linux tracing support is wonderful, and not just for LTT - perf, ftrace and systemtap are awesome tools (and more powerful than LTTng in some ways). In fact perf can do all what the web page says and it seems to be more simple for my taste

Re:See the light?

[francis-giraldeau]

We are waiting for decent kernel tracing since a decade, while LTTng is readily available today. It's better than any other tools like perf, ftrace and dtrace. Microsoft Windows has the Event Tracing for Windows since 2003, and if Linux wants to be taken seriously, it has to be mainline and available without kernel patching. And, I think that users should not be experts to use that kind of tools.

Re:Ubuntu Only?

[francis-giraldeau]

Binary packages are easy to install, that's it. I don't know of other LTTng integration inside a distro. If you prefer patching your own kernel and compiling tools from git repository, you're free to do it.

trace or analysis tool?

[hraponssi]

are you talking about a trace or a data analysis tool? if you plan to use LTT to get a trace and then help the user analyse it, maybe you are more into analysis than tracing. then your question could be a bit misleading. Anyway, you would probably end up trying it all out, adding some features to make it all easier to trace as you try to use the existing stuff and analyse the results and so on as you progress. And if you are into trace data analysis (as opposed to tracing) then your domain of kernel trace data analysis is just one application of data analysis. there you need to look into data analysis methods, statistical methods, machine learning, etc. depending on what kind of analysis you like and need. it is somewhat different depending on your goals such as performance data, behaviour trace and analysis, etc.. for some more behaviour related stuff you can look into domains of program comprehension, behaviour analysis and modeling in general, software reverse engineering, specification mining, etc. anyway, at least i would be interested to see some results on this kind of stuff if you go with it and have some means to follow on it and provide feedback..mainstream or not most of this stuff never ends up anywhere or is available at all.

Re:See the light?

[Anonymous Coward]

"if Linux wants to be taken seriously..."

Funny the one thing needed to be taken seriously is, by magic, the subject of your thesis.

Had you been working on, say, resizable ramdisks (I'm just making this up), then resizable ramdisks would have been the one thing needed in Linux for Linux to be taken seriously.

Ever considered humility?

Re:See the light?

[h4rr4r]

Linux is taken quite seriously and to use this sort of tool and not be an expert is pointless.

Re:See the light?

[Anonymous Coward]

and if Linux wants to be taken seriously

Linux isn't taken seriously at all! It only has close to 50% of the server market-share and a near monopoly on supercomputers. Look, when you have something workable we might talk, but until then you're just another PHD that has produced absolutely nothing of value.