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flutter / third_party / perfetto / 0e98b42c5be529a8b27ec4ae02c16843f9c6277d
commit0e98b42c5be529a8b27ec4ae02c16843f9c6277d[log] [tgz]
authorJoeNotCharlesGoogle <joenotcharles@google.com>Wed Aug 20 16:48:03 2025 -0400
committerGitHub <noreply@github.com>Wed Aug 20 16:48:03 2025 -0400
tree9280c1ff3473d7ccc610be12f29ec6980313f619
parent0e22509ccc96e2bd79bfdcd1885d1fe6b1369ef8 [diff]
Make process_type and thread_type into ints (#2633)

This removes the ProcessType enum from chrome_process_descriptor.proto and, for symmetry, moves the ThreadType enum from chrome_thread_descriptor.proto to chrome_enums.proto. The enum values are now controlled from Chrome.

The process_type and thread_type field are changed to int32 instead of naming the enum type. This is wire-compatible according to https://protobuf.dev/programming-guides/proto2/#wire-safe-changes. Specifying the enum type would require importing protos/third_party/chromium/chrome_enums.proto from inside protos/perfetto/trace/track_event, which is a dependency inversion. It would cause duplicate dependency when building Perfetto in Chrome, which would import the same enum from both base/protos/chrome_enums.proto and (indirectly) from third_party/perfetto/protos/third_party/chromium/chrome_enums.proto.

Unfortunately all test expectations in .textproto format now need to use numeric process and thread types, since the test output doesn't treat the fields as enums.

Ints are used instead of extension fields because managing the extension descriptor adds extra failure points: serializing an extension descriptor that defines `process_type` and `thread_type` into a trace will cause older trace_processor builds that define those fields as non-extensions to reject the trace, so this extension would need special handling in Chrome.
24 files changed
tree: 9280c1ff3473d7ccc610be12f29ec6980313f619
  1. .github/
  2. bazel/
  3. build_overrides/
  4. buildtools/
  5. debian/
  6. docs/
  7. examples/
  8. gn/
  9. include/
  10. infra/
  11. protos/
  12. python/
  13. src/
  14. test/
  15. third_party/
  16. tools/
  17. ui/
  18. .bazelignore
  19. .bazelrc
  20. .bazelversion
  21. .clang-format
  22. .clang-tidy
  23. .git-blame-ignore-revs
  24. .gitallowed
  25. .gitattributes
  26. .gitignore
  27. .gn
  28. .style.yapf
  29. Android.bp
  30. Android.bp.extras
  31. BUILD
  32. BUILD.extras
  33. BUILD.gn
  34. CHANGELOG
  35. codereview.settings
  36. CONTRIBUTORS.txt
  37. DIR_METADATA
  38. heapprofd.rc
  39. LICENSE
  40. meson.build
  41. METADATA
  42. MODULE.bazel
  43. MODULE.bazel.lock
  44. MODULE_LICENSE_APACHE2
  45. OWNERS
  46. perfetto.rc
  47. perfetto_flags.aconfig
  48. PerfettoIntegrationTests.xml
  49. persistent_cfg.pbtxt
  50. README.chromium
  51. README.md
  52. TEST_MAPPING
  53. traced_perf.rc
  54. WATCHLISTS
  55. WORKSPACE
README.md

Perfetto - System profiling, app tracing and trace analysis

Perfetto is an open-source suite of SDKs, daemons and tools which use tracing to help developers understand the behaviour of complex systems and root-cause functional and performance issues on client and embedded systems.

It is a production-grade tool that is the default tracing system for the Android operating system and the Chromium browser.

Core Components

Perfetto is not a single tool, but a collection of components that work together:

  • High-performance tracing daemons: For capturing tracing information from many processes on a single machine into a unified trace file.
  • Low-overhead tracing SDK: A C++17 library for direct userspace-to-userspace tracing of timings and state changes in your application.
  • Extensive OS-level probes: For capturing system-wide context on Android and Linux (e.g. scheduling states, CPU frequencies, memory profiling, callstack sampling).
  • Browser-based UI: A powerful, fully local UI for visualizing and exploring large, multi-GB traces on a timeline. It works in all major browsers, requires no installation, and can open traces from other tools.
  • SQL-based analysis library: A powerful engine that allows you to programmatically query traces using SQL to automate analysis and extract custom metrics.

Why Use Perfetto?

Perfetto was designed to be a versatile and powerful tracing system for a wide range of use cases.

  • For Android App & Platform Developers: Debug and root-cause functional and performance issues like slow startups, dropped frames (jank), animation glitches, low memory kills, and ANRs. Profile both Java/Kotlin and native C++ memory usage with heap dumps and profiles.
  • For C/C++ Developers (Linux, macOS, Windows): Use the Tracing SDK to instrument your application with custom trace points to understand its execution flow, find performance bottlenecks, and debug complex behavior. On Linux, you can also perform detailed CPU and native heap profiling.
  • For Linux Kernel & System Developers: Get deep insights into kernel behavior. Perfetto acts as an efficient userspace daemon for ftrace, allowing you to visualize scheduling, syscalls, interrupts, and custom kernel tracepoints on a timeline.
  • For Chromium Developers: Perfetto is the tracing backend for chrome://tracing. Use it to debug and root-cause issues in the browser, V8, and Blink.
  • For Performance Engineers & SREs: Analyze and visualize a wide range of profiling and tracing formats, not just Perfetto's. Use the powerful SQL interface to programmatically analyze traces from tools like Linux perf, macOS Instruments, Chrome JSON traces, and more.

Getting Started

We‘ve designed our documentation to guide you to the right information as quickly as possible, whether you’re a newcomer to performance analysis or an experienced developer.

  1. New to tracing? If you're unfamiliar with concepts like tracing and profiling, start here:

  2. Ready to dive in? Our “Getting Started” guide is the main entry point for all users. It will help you find the right tutorials and documentation for your specific needs:

  3. Want the full overview? For a comprehensive look at what Perfetto is, why it's useful, and who uses it, see our main documentation page:

Community & Support

Have questions? Need help?

We follow Google's Open Source Community Guidelines.