The OLT viewer presents a visualization of the flow of events in the communication between objects in a distributed program. Each trace symbol appears on a line representing a separate process, as shown in the figure below, and also as text in the status bar. Parentheses enclose a complete call-reply sequence.
The table below presents each trace symbol, its corresponding status line text, and a description of the type of event that it represents.
Symbol | Status line text | Type of event |
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start | object created or retrieved |
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call | method call from client |
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receive call | entry point to debuggable method of an object |
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reply | method call completed from an object |
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receive reply | method call completed from client |
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receive call | call from a debuggable object to itself (nested) |
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reply | call from an object to itself (nested) |
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one-way call | method call from client, no reply expected |
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receive one-way call | entry point to an object method |
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untraceable call | call from client, recipient is untraceable |
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exit | stop, or object destroyed or released |
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receive call | application exception |
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call or reply | event waiting for partner to arrive |
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call-reply sequence | Parentheses denote the limits of a call-reply sequence |
Selected event
Partial-order display
Real-time display
How to read the trace
Preparing for an OLT and IBM Distributed Debugger session
Navigating the trace