Perfetto: Add PSI sampling support Add support for sampling PSI values from `/proc/pressure/*`. Polling is configured similarly to other metrics from `/proc/`, by `psi_period_ms`. Initial support only captures the total stall time for a given resource (cpu/io/mem) and stall type (some/full). However, this can easily be extended to include the 10s/60s/300s historical ratio averages. The following new counters are grouped with other system state counters: * psi.mem.some * psi.mem.full * psi.io.some * psi.io.full * psi.mem.some * psi.mem.full Bug: 315152880 Test: Locally build + capture trace with psi_period_ms set to 100 Test: perfetto_unittests Change-Id: Ieee27569f2851b9f8723f68bee2fea40cfd9b0e2
Perfetto is a production-grade open-source stack for performance instrumentation and trace analysis. It offers services and libraries and for recording system-level and app-level traces, native + java heap profiling, a library for analyzing traces using SQL and a web-based UI to visualize and explore multi-GB traces.
See https://perfetto.dev/docs or the /docs/ directory for documentation.