commit | 9dacc8523a6274cc2b29ceed93fcfc3c61e75e1d | [log] [tgz] |
---|---|---|
author | Lalit Maganti <lalitm@google.com> | Tue Sep 18 13:28:32 2018 +0100 |
committer | Lalit Maganti <lalitm@google.com> | Tue Sep 18 13:28:32 2018 +0100 |
tree | ea570095cf843d8d434ef481e143e78e5a7bb771 | |
parent | b98184a9ff697b5706fb331675354a36c7c0fa41 [diff] |
trace_processor: collapse sched slice table to a flat table Instead of storing sched events per-cpu, store them all in a flat map. This makes queries significantly faster on large traces as we do not constantly need to search for the next index across CPUs. Instead we can skip across the vector using std find on a vector<bool> which is very fast. While this happens, also remove ts_lower_bound, ts_clip and quantum. quantum and ts_clip can either be expressed as a combination of a span join with a window table or a quantum table. ts_bound is used just for displaying tracks accurately in the UI and can be replaced by clipping instead. Change-Id: I1715658b17fcf83c13eebbd8ef01b46f85503b90
Perfetto is an open-source project for performance instrumentation and tracing of Linux/Android/Chrome platforms and user-space apps.
It consists of:
A portable, high efficiency, user-space tracing library
designed for tracing of multi-process systems, based on zero-alloc zero-copy zero-syscall (on fast-paths) writing of protobufs over shared memory.
OS-wide Linux/Android probes for platform debugging
Web-based frontend
A UI for inspection and analysis of traces (coming soon).
Batch processing of traces
A python / C++ (TBD) library for trace-based metrics (coming soon).
Perfetto is building the next-gen unified tracing ecosystem for:
The goal is to create an open, portable and developer friendly tracing ecosystem for app and platform performance debugging.
Designed for production
Perfetto's tracing library and daemons are designed for use in production. Privilege isolation is a key design goal:
See docs/security-model.md for more details.
Long traces
Pefetto aims at supporting hours-long / O(100GB) traces, both in terms of recording backend and UI frontend.
Interoperability
Perfetto traces (output) and configuration (input) consists of protobuf messages, in order to allow interoperability with several languages.
See docs/trace-format.md for more details.
Composability
As Perfetto is designed both for OS-level tracing and app-level tracing, its design allows to compose several instances of the Perfetto tracing library, allowing to nest multiple layers of tracing and drive then with the same frontend. This allows powerful blending of app-specific and OS-wide trace events. See docs/multi-layer-tracing.md for more details.
Portability
The only dependencies of Perfetto's tracing libraries are C++11 and Protobuf lite (plus google-test, google-benchmark, libprotobuf-full for testing).
Extensibility
Perfetto allows third parties to defined their own protobufs for:
Allowing apps to define their own strongly-typed input and output schema. See docs/trace-format.md for more details.