Traces are saved as PERFETTO-TRACE files. To create one: Enable developer options. Open Developer Options settings. By default, Perfetto keeps full trace buffers in memory. It writes them when tracing...
Traces are saved as PERFETTO-TRACE files. To create one: Enable developer options. Open Developer Options settings. By default, Perfetto keeps full trace buffers in memory. It writes them when tracing ends. This reduces overhead but limits trace size to device memory. To capture larger traces: Use write_into_file field. It periodically writes buffers to the file.
The article offers helpful knowledge. The discussion of Y stands out.
On Android 10, traces use Perfetto format. They are saved under /data/local/traces with .perfetto-trace extension. Website to parse them: https://ui.perfetto.dev/#!/record.
First method to use Perfetto: Capture traces on the device. Android 9+ devices have System Tracing app. It allows recording without ADB. Turn on Developer Options.
To use ADB: Specify output path or stdout. perfetto writes output to that file.
Light mode selects some data sources. Normal mode allows more customization. Use –config to specify config file.
ETL logs traces to a file. WPR starts/stops tracing. It uses a profile file (.wprp) to configure what to trace. WPR can directly launch on desktop. The web interface is used on HoloLens.
Combining eBPF and Perfetto can diagnose latency in huge traces. See “eBPF Example”.
TracePackets form a sequence. Service doesn’t know their contents. If invalid, no more packets come. Packets from different writers can be in any order. The consumer can reorder them.
The Perfetto ecosystem covers system profiling, in-app tracing, trace viewer and analysis. We extended the processor’s cross-platform support to Windows. This enabled new tooling on Windows using .NET Core and C#. It does unique post-processing and exposes data to Windows Performance Analyzer.