LTTng Viewer

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The Linux Trace Toolkit Next Generation Viewer (LTTV) is a graphical application for viewing and analyzing traces recorded with LTTng (http://lttng.org). It is being developed mainly at Ecole Polytechnique de Montreal and released under the GNU GPL.

[edit] Description

[edit] General characteristics

LTTV is designed to be very modular. Its powerful plugin system makes it easy to add features.

LTTV is optimized for handling very large traces and has been tested successfully with 15 GB traces.

Resource view showing a virtual machine (Trace 1) and its host (Trace 0)

LTTV is capable of opening several traces at once and merging their data. This makes it possible to view traces of virtual machines and their host simultaneously in order to study problems that involve the interaction between them. In order for this to work correctly, timestamping in all the traces must be consistent.

[edit] Graphical interface

The following graphical views are included in the LTTV distribution.

[edit] Histogram

This is a graph of the density of events through time. It makes it easy to find periods of high system activity. Filters can be applied so the graph applies only to specific event types.

Histogram showing increased activity while find process is running

[edit] Control flow view

The Control flow view displays the state of every process in the system through time.

Resource view, control flow view and detailed events view on a 2-cpu system

[edit] Resource view

The Resource view displays, in graph form, the state of CPUs, IRQ handlers, SoftIRQ handlers and trap handlers of the system through time.

[edit] Detailed events view

This is a list of all the events in the trace. Among other information, the event name, its precise timestamp as well as its arguments are shown. Filters can be applied so only events corresponding to given criteria are displayed.

[edit] Statistics viewer

The statistics viewer displays various statistics concerning the system states during the trace.

[edit] Interrupts statistics

This plugin computes a variety of statistics concerning interrupts: frequency, total time in handler, max time in handler.

[edit] Text-based output

LTTV also has a number of text-based plugins. It is, for instance, possible to output a trace in text form in a one-event-per-line format.