From: Mathieu Desnoyers Date: Wed, 20 Jul 2011 01:48:47 +0000 (-0400) Subject: Add readme X-Git-Tag: v2.0-pre1~15 X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=98541fcfb395ad8bc7f1dc347694b3ce5527c4c7;p=lttng-modules.git Add readme Signed-off-by: Mathieu Desnoyers --- diff --git a/README b/README new file mode 100644 index 00000000..48ac6572 --- /dev/null +++ b/README @@ -0,0 +1,39 @@ +LTTng 2.0 modules + +Mathieu Desnoyers +July 19, 2011 + +LTTng 2.0 kernel modules build against a vanilla or distribution kernel, without +need for additional patches. Other features: + +- Produces CTF (Common Trace Format) natively, + (http://www.efficios.com/ctf) +- Function tracer, perf counters and kprobes support, +- Integrated interface for both kernel and userspace tracing, +- Have the ability to attach "context" information to events in the + trace (e.g. any perf counter, pid, ppid, tid, comm name, etc). So + basically, all the perf "required fields" like "preempt count" and + "bkl count" are all optional, specified on a per-tracing-session basis + (except for timestamp and event id, which are mandatory). + +To build and install, you will need to have your kernel headers available (or +access to your full kernel source tree), and use: + +make +make install + +If you need to specify the target directory to the kernel you want to build +against, use: + +KERNELDIR=path_to_kernel_dir make +KERNELDIR=path_to_kernel_dir make install + +Use lttng-tools to control the tracer. LTTng tools should automatically load the +kernel modules when needed. + +So far, it has been tested on vanilla kernels 2.6.38 and 2.6.39 (on x86 at the +moment). It should work fine with newer kernels and other architectures, but +expect build issues with kernels older than 2.6.36. The clock source currently +used is the standard gettimeofday (slower, less scalable and less precise than +the LTTng 0.x clocks). Support for LTTng 0.x clocks will be added back soon into +LTTng 2.0.