# Trebuchet

Trebuchet is a Kotlin library for parsing and analyzing Android trace files generated by the `atrace` or `systrace` commands.  This is not an officially supported Google product.

## Library

The code for the Trebuchet library can be found in the `core/` directory.

## Bundled Programs

Trebuchet comes bundled with several programs for analyzing one or more trace files.

### Startup Analyzer

The Startup Analyzer program takes a trace file, detects any startup events that occurred during the traced time period, and prints information about the events.  If Trebuchet is built using the Android build system, there will be a StartupAnalyzerKt program placed into a directory that is a member of the PATH system variable.  If you wish to use Gradle, you can use the `startup-analyzer.sh` script located in the `scripts/` directory.

### Startup Summarizer

The Startup Summarizer program takes a set of trace files, detects startup events in each file, and computes average and standard deviation for startup stats, broken down by program name, compiler filter, and cache status.  If Trebuchet is built using the Android build system, there will be a StartupSummarizerKt program placed into a directory that is a member of the PATH system variable.  If you wish to use Gradle, you can use the `startup-summarizer.sh` script located in the `scripts/` directory.

## Helper Scripts

The `scripts/` directory contains a shell script called `run-startup.sh`, which will start a trace, launch an activity given a package name and an activity name, transfer the trace file to the host machine, and run the StartupAnalyzer.