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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?"
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? ;-)
A problem already solved with DTrace on Solaris http://docs.sun.com/app/docs/doc/817-6223
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?
Atlas stands on the earth and carries the celestial sphere on his shoulders.
Kernel tracing instrumentation is ready, now we need decent analysis tools. The problem is that there is so much data, that it's hard to interpret them. For the project, I have to come up with something that is new and better that what is already known. For example, we could get a better analysis than bootchart, or auto detect bottlenecks in a system (disk, CPU, memory, network, etc...). There are some work done to integrate userspace and kernel space tracing, virtual machine and host traces, dynamic and static trace points. For a distro, they could record a trace in background and send this information allong with the core dump when an application crash occur. That's all ideas!
Also, I wonder why LTTng is not mainline yet
Well, a bit of searching would have answered your question
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
Right. Because everyone knows the best place to develop, debug, and profile code is on a production machine, and the person doing the development should be a system administrator, preferably with minimal experience.
I would say many people do know that the best place to understand the performance of a system in production is in production. If the vendors support techs can give an admin commands to run and know that a typo here or there will not result in a panic then that is a very useful feature.