2022-08-29 16:24:29 +02:00
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This is the documentation of ovni, the Obtuse (but Versatile) Nanoscale
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Instrumentation project.
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!!! Note
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Preferably write the name of the project as lowercase *ovni*
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unless the grammar rules suggest otherwise, such as starting a
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new sentence.
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2022-08-29 17:10:38 +02:00
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The ovni project implements a fast instrumentation library that records
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small events (starting at 12 bytes) during the execution of programs to
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later investigate how the execution happened.
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2022-08-29 16:24:29 +02:00
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The instrumentation process is split in two stages: [runtime](runtime)
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tracing and [emulation](emulation/).
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During runtime, very simple and short events are stored on disk which
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describe what is happening. Once the execution finishes, the events are
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read and processed to reproduce the execution during the emulation
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process, and the final execution trace is generated.
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By splitting the runtime and emulation processes we can perform
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expensive computations during the trace generation without disturbing
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the runtime process.
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Each event belongs to a model, which has a direct mapping to a target
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library or program. Each model is independent of other models, and they
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can be instrumented concurrently.
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The events are classified by using three identifiers known as *model*,
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*category* and *value* (or MCV for short).
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