| commit | 00c8667671074addfc312f54d8c69f84e3fb0070 | [log] [tgz] |
|---|---|---|
| author | Lalit Maganti <lalitm@google.com> | Fri Jul 17 16:38:17 2020 +0100 |
| committer | Lalit Maganti <lalitm@google.com> | Fri Jul 17 16:38:17 2020 +0100 |
| tree | 54fa8d9eca905049bc50b7f94fafbca55932f433 | |
| parent | 49c563bbc16f92cded2548a67229b845ab23e494 [diff] |
tp: parse tracing_started event and drop ftrace packets before it ftrace can occasionally be buggy and may lead to events being included in the trace from well before the tracing started. Until now we've just included these events in the trace even though they really shouldn't be. This CL introduces parsing of the tracing_started TraceServiceEvent which gives the timestamp where tracing started (before any producer is informed of tracing being ready). We then use this timestamp and filter out all events before it. This filtering is restricted to ftrace only as it's the only data source fully under our control - if other producers want to write data from before trace start, that's their choice. Bug: 154156099 Change-Id: I8be103d091cd13c85a695688ae7e13c852b93e25
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.