32 lines
1.1 KiB
Markdown
32 lines
1.1 KiB
Markdown
# Overview
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The objective of the ovni project is to provide insight into what
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happened at execution of a program.
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The key pieces of software involved are instrumented so they emit events
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during the execution which allow the reconstruction of the execution
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later on.
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During the execution phase, the information gathered in the events is
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kept very short and simple, so the overhead is kept at minimum to avoid
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disturbing the execution process. Here is an example of a single event
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emitted during the execution phase, informing the current thread to
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finish the execution:
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00 4f 48 65 52 c0 27 b4 d3 ec 01 00
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During the emulation phase, the events are read and processed in the
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emulator, reconstructing the execution. State transitions are recorded
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in a Paraver trace. Here is an example of the same thread ceasing the
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execution:
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2:0:1:1:1:50105669:1:0
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Finally, loading the trace in the Paraver program, we can generate a
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timeline visualization of the state change. Here is the example for the
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same state transition of the thread stopping the execution:
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