The trace consists of trace lines and event symbols. The colors referred to below are the OLT's default colors. You can change these by selecting File > Preferences > OLT > Display > Colors. (If you do not see Display, click on the button beside OLT.)
Trace lines
A trace line is a horizontal line connecting a sequence of events (object method
calls), which run under a single thread of execution. Each trace line represents
either an object, servlet, or EJB residing on an application server, or the
client application or servlet that initiated a method call to the server. The
name of each trace is shown to the left of the line:
Each trace line name consists of four parts, representing the following information:
1 | host name |
2 | process ID![]() |
3 | on a client trace: client ID1 on an object trace: object ID |
4 | on a client trace: Client on an object trace: object name |
1For C++ clients, the client ID is the thread ID for the client.
To help you navigate on the trace, every fourth line is colored blue.
Events
An "event" is a call to a method, a return from a method call, or the
start or end of a process. Object method calls are shown on the trace as
circles. Start and exit events are shown as squares. An arrow connects paired
events, with the arrowhead representing the direction of data flow.
Identifying predecessor and successor events
Predecessor and successor events are those events that follow or precede a
particular event in its own thread, and related events in other threads. To
identify all predecessors and successors to a particular event, position the
mouse pointer over an event and hold down Ctrl, while clicking
on the event. All predecessor events are colored red, and all successor events
are colored green.
Status lines
The status lines at the bottom of the window provide information identifying the
location of the "selected" event and the "current" event.
The selected event (highlighted green by default) is the last event you clicked
with the left mouse button. The current event is the event that your mouse
pointer is currently positioned over. As you move your pointer, the current
event changes.
This textual representation of each event consists of seven parts, representing the following information:
1 | event type |
2 | method name |
3 | host name |
4 | process ID |
5 | on a client trace: client ID1 on an object trace: object ID |
6 | on a client trace: Client on an object trace: object name |
7 | position on the trace |
1For C++ clients, the client ID is the thread ID for the client.
Trace symbols
Selected event
Partial-order display
Real-time display
Performance analysis