LTTng is an open source tracing framework for Linux.

System-wide insight

LTTng allows to understand the interactions between multiple components of a given system, i.e.:

Tracing all those components with LTTng produces a unified log of events, providing great insight into the system's behavior. Here's a simplified example of a system trace:

Time App. Event Payload
17:23:05.035454 my-app startup
17:23:05.043948 my-app readConfigBegin path=/home/mole/.my-app/config
17:23:05.044120 linux sys_open pathname=/home/mole/.my-app/config
17:23:05.044120 linux sys_fstat fd=5
ret={st_uid=1002, st_size=4608, ...}
17:23:05.044498 linux sys_read fd=5
17:23:05.046005 linux sys_close fd=5
17:23:05.047948 my-app readConfigEnd
17:23:06.164870 my-app getUser username=joe
17:23:06.251164 java-db doQuery handle=23
query=SELECT * FROM users WHERE...
... ... ... ...

High performance

LTTng is designed from the ground up to provide low overhead tracing on production systems. The tracers achieve this great performance through a combination of essential techniques such as per-CPU buffering, RCU data structures, a compact and efficient binary trace format, and more.

LTTng disturbs the traced system as little as possible in order to make tracing of subtle race conditions and rare interrupt cascades possible.

On platforms where resources are limited, such as some Linux embedded systems, you can use LTTng out of the box to help developers pinpoint the sources of hard-to-debug issues.

LTTng offers a new approach to gain insight into your system's behavior.


Whether your target is a small embedded system or a large cloud, LTTng provides flexible configuration options that can accommodate the system's workload. LTTng supports architectures such as IA-32 (x86), x86-64, PowerPC, ARM, and MIPS, amongst others.

LTTng's tracing session mechanism makes it possible to record multiple traces concurrently with different configuration options. Each Unix user may create and configure as many tracing sessions as needed.

Depending on your specific scenario, you may wish, for example, to:


As LTTng is packaged for many major Linux distributions, you can often use your package manager to install it.

As a user, you control the tracers with a single tool, the lttng command-line interface.

Multiple tools are available to view and analyze the traces that LTTng produces: GUI, CLI tools, and custom scripts.

LTTng has a lot more to offer. To learn more: