google/perfetto
Oct 2024 – Oct 2025
13 Months active
Languages Used
C++GNJavaScriptPythonSQLTypeScriptBPMarkdown
Technical Skills
Build SystemC++C++ DevelopmentComponent DesignComponent RefactoringDebugging
Lalit Maganti
PROFILE
Lalit Maganti
Lalit Mittal led core development on google/perfetto, building advanced trace processing and profiling features that improved data analysis workflows and system observability. He architected and migrated key components to a dataframe-backed model, enabling scalable, high-performance queries and more reliable data handling. Using C++, Python, and TypeScript, Lalit refactored the Trace Processor’s core, optimized build systems, and enhanced the UI with features like multi-trace loading and flamegraph improvements. His work addressed stability, cross-platform compatibility, and performance bottlenecks, delivering robust solutions for trace data ingestion, visualization, and automation. The depth of his engineering ensured maintainable, extensible infrastructure for ongoing profiling needs.
Overall Statistics
Feature vs Bugs
61%Features
Repository Contributions
697Total
Bugs
161
Commits
697
Features
247
Lines of code
315,435
Activity Months13
Your Network
4376 people
Work History
October 2025
35 Commits • 9 Features
Oct 1, 2025October 2025 summary: Delivered a cohesive set of UI, build-tools, and trace-processor enhancements for Perfetto, elevating profiling UX, reliability, and developer productivity. Key UI improvements include the Pprof Profiles plugin with counter-track enlargement, flamegraph tooltip placement, and test tooling enhancements (--no-depscheck). Build-tools and repository configuration were modernized with macOS x64 Emscripten support, validation of origin/main as a parent, and expanded gitignore for local.md and rfcs. Trace Processor and TP work added simpleperf proto format support, faster connect flow, post-finalization access to V8 table columns, JSON integration for sorting/indexing, and a modular architecture with docs support. A rigorous stability/fixes effort addressed API data races, MSAN issues, crash scenarios, and parsing edge cases, while memory- and callstack-related improvements reduced overhead and improved data integrity. These changes collectively accelerate profiling workflows, improve data reliability, and ease future maintenance.
35 Commits • 9 Features
Oct 1, 2025October 2025 summary: Delivered a cohesive set of UI, build-tools, and trace-processor enhancements for Perfetto, elevating profiling UX, reliability, and developer productivity. Key UI improvements include the Pprof Profiles plugin with counter-track enlargement, flamegraph tooltip placement, and test tooling enhancements (--no-depscheck). Build-tools and repository configuration were modernized with macOS x64 Emscripten support, validation of origin/main as a parent, and expanded gitignore for local.md and rfcs. Trace Processor and TP work added simpleperf proto format support, faster connect flow, post-finalization access to V8 table columns, JSON integration for sorting/indexing, and a modular architecture with docs support. A rigorous stability/fixes effort addressed API data races, MSAN issues, crash scenarios, and parsing edge cases, while memory- and callstack-related improvements reduced overhead and improved data integrity. These changes collectively accelerate profiling workflows, improve data reliability, and ease future maintenance.
October 2025
September 2025
70 Commits • 33 Features
Sep 1, 2025September 2025 performance summary for google/perfetto focused on delivering high-value profiling features, improving UI accuracy, and strengthening cross‑platform reliability. Key features from the period include automatic CPU profiles on startup, improved source/line number aggregation, and the ability to compute the critical path without requiring a process name, along with trace-cmd -N output support and startup-driven breakdown analysis. A UI canary release was rolled to validate changes while TP core improvements introduced SQL parser regeneration and function API migrations, contributing to faster build times and more stable APIs.
September 2025
70 Commits • 33 Features
Sep 1, 2025September 2025 performance summary for google/perfetto focused on delivering high-value profiling features, improving UI accuracy, and strengthening cross‑platform reliability. Key features from the period include automatic CPU profiles on startup, improved source/line number aggregation, and the ability to compute the critical path without requiring a process name, along with trace-cmd -N output support and startup-driven breakdown analysis. A UI canary release was rolled to validate changes while TP core improvements introduced SQL parser regeneration and function API migrations, contributing to faster build times and more stable APIs.
August 2025
83 Commits • 39 Features
Aug 1, 2025August 2025 — Google Perfetto: Delivered substantial UI and trace-processor architectural refinements along with reliability and tooling improvements. Key features include UI Enhancements with multi-trace loading and y-axis sharing for counter tracks, as well as UI plugin groupings (cpufreq and sched) to improve navigation and usability. The Trace Processor saw major restructuring: proto/tests refactor and decoupling of sorting from TraceProcessorContext, plus per-trace/context organization improvements. Major bug fixes targeted correctness and performance, including sorting with negative timestamps, startup breakdown performance, and stability for ninja traces. Kernel symbolization and perf data work expanded capabilities with kernel-frame symbolization, kernel version exposure from perf data, and support for non-CPU scoped perf counters. CI, tooling, and automation improvements added Gemini GH Action and presubmit root-discovery enhancements, along with UI startup commands/macros to enable scripted workflows.
83 Commits • 39 Features
Aug 1, 2025August 2025 — Google Perfetto: Delivered substantial UI and trace-processor architectural refinements along with reliability and tooling improvements. Key features include UI Enhancements with multi-trace loading and y-axis sharing for counter tracks, as well as UI plugin groupings (cpufreq and sched) to improve navigation and usability. The Trace Processor saw major restructuring: proto/tests refactor and decoupling of sorting from TraceProcessorContext, plus per-trace/context organization improvements. Major bug fixes targeted correctness and performance, including sorting with negative timestamps, startup breakdown performance, and stability for ninja traces. Kernel symbolization and perf data work expanded capabilities with kernel-frame symbolization, kernel version exposure from perf data, and support for non-CPU scoped perf counters. CI, tooling, and automation improvements added Gemini GH Action and presubmit root-discovery enhancements, along with UI startup commands/macros to enable scripted workflows.
August 2025
July 2025
105 Commits • 49 Features
Jul 1, 2025July 2025 (google/perfetto) — Delivered notable performance optimizations, reliability fixes, and tooling improvements that directly enhance trace processing speed, stability, and release readiness. Key outcomes include faster flamegraph generation, reduced database overhead, and more robust UI behavior and caching strategies.
July 2025
105 Commits • 49 Features
Jul 1, 2025July 2025 (google/perfetto) — Delivered notable performance optimizations, reliability fixes, and tooling improvements that directly enhance trace processing speed, stability, and release readiness. Key outcomes include faster flamegraph generation, reduced database overhead, and more robust UI behavior and caching strategies.
June 2025
82 Commits • 18 Features
Jun 1, 2025June 2025 performance summary for google/perfetto: Delivered major data-workflow and stability improvements across dataframe-backed components and the Trace Processor. Key outcomes include: (1) Dataframe core TP enhancements with sorting overhaul, duplicate value tracking, and id-like column storage optimization, enabling faster, more accurate query planning; (2) Trace Processor core stability improvements, including graceful handling of empty frames, improved dominator-tree performance, and removal of hardcoded limits; boot clock behavior adjustments; (3) Substantial groundwork for dataframe-backed tables across Perfetto, migrating core tables and static functions to dataframe-backed implementations to unlock scalable data modeling; (4) targeted performance optimizations and build-time improvements reducing compile times and memory churn; (5) ecosystem improvements with Python API enhancements, packaging fixes, docs updates, and CI reliability improvements; resulting in stronger reliability, faster analysis, and a cleaner migration path to dataframe-backed architecture.
82 Commits • 18 Features
Jun 1, 2025June 2025 performance summary for google/perfetto: Delivered major data-workflow and stability improvements across dataframe-backed components and the Trace Processor. Key outcomes include: (1) Dataframe core TP enhancements with sorting overhaul, duplicate value tracking, and id-like column storage optimization, enabling faster, more accurate query planning; (2) Trace Processor core stability improvements, including graceful handling of empty frames, improved dominator-tree performance, and removal of hardcoded limits; boot clock behavior adjustments; (3) Substantial groundwork for dataframe-backed tables across Perfetto, migrating core tables and static functions to dataframe-backed implementations to unlock scalable data modeling; (4) targeted performance optimizations and build-time improvements reducing compile times and memory churn; (5) ecosystem improvements with Python API enhancements, packaging fixes, docs updates, and CI reliability improvements; resulting in stronger reliability, faster analysis, and a cleaner migration path to dataframe-backed architecture.
June 2025
May 2025
41 Commits • 17 Features
May 1, 2025May 2025 performance snapshot for google/perfetto focusing on stabilizing the Trace Processor (TP) and expanding dataframe capabilities, while strengthening CI and cross‑platform readiness. The team delivered indexing-enabled dataframes, expanded dataframe APIs, and core TP stability fixes, underpinned by tooling improvements and CI fixes to reduce production risk and improve developer velocity.
May 2025
41 Commits • 17 Features
May 1, 2025May 2025 performance snapshot for google/perfetto focusing on stabilizing the Trace Processor (TP) and expanding dataframe capabilities, while strengthening CI and cross‑platform readiness. The team delivered indexing-enabled dataframes, expanded dataframe APIs, and core TP stability fixes, underpinned by tooling improvements and CI fixes to reduce production risk and improve developer velocity.
April 2025
53 Commits • 18 Features
Apr 1, 2025April 2025 monthly summary focusing on delivering foundational and scalable DataFrame capabilities in Perfetto, strengthening data processing, reliability, and developer tooling. Key work spanned dataframe core enhancements (TP and DF) to enable dataframe cursor, sqlite integration, numeric and string column support, null overlays, isnull/isnotnull, and sorting capabilities, plus a runtime builder for unknown schemas. Engine-side dataframe handling made progress with sorting, distinct, limit/offset, and min/max optimizations, along with row/cost estimation; groundwork for shared dataframes and broader dataframe integration. A major table engine refactor prepared for dataframe integration, including commit/rollback hook delivery to all virtual table modules and support for choosing backends in create perfetto table. UI/stdlib and tooling improvements improved usability and developer experience (UI fixes, naming improvements, moving Perfetto links to GitHub, presubmit formatting, and CI enhancements for dev branches). Code quality initiatives included full code formatting passes and documentation fixes.
53 Commits • 18 Features
Apr 1, 2025April 2025 monthly summary focusing on delivering foundational and scalable DataFrame capabilities in Perfetto, strengthening data processing, reliability, and developer tooling. Key work spanned dataframe core enhancements (TP and DF) to enable dataframe cursor, sqlite integration, numeric and string column support, null overlays, isnull/isnotnull, and sorting capabilities, plus a runtime builder for unknown schemas. Engine-side dataframe handling made progress with sorting, distinct, limit/offset, and min/max optimizations, along with row/cost estimation; groundwork for shared dataframes and broader dataframe integration. A major table engine refactor prepared for dataframe integration, including commit/rollback hook delivery to all virtual table modules and support for choosing backends in create perfetto table. UI/stdlib and tooling improvements improved usability and developer experience (UI fixes, naming improvements, moving Perfetto links to GitHub, presubmit formatting, and CI enhancements for dev branches). Code quality initiatives included full code formatting passes and documentation fixes.
April 2025
March 2025
31 Commits • 8 Features
Mar 1, 2025March 2025 focused on enabling deeper observability and foundational data modeling, while tightening stability and release processes. Delivered a new TraceWriter drop-count API, established a DataFrame core and APIs, improved UI test coverage and labeling, and hardened CI workflows, resulting in stronger business value through better tracing reliability, data capabilities, and faster, safer releases.
March 2025
31 Commits • 8 Features
Mar 1, 2025March 2025 focused on enabling deeper observability and foundational data modeling, while tightening stability and release processes. Delivered a new TraceWriter drop-count API, established a DataFrame core and APIs, improved UI test coverage and labeling, and hardened CI workflows, resulting in stronger business value through better tracing reliability, data capabilities, and faster, safer releases.
February 2025
20 Commits • 4 Features
Feb 1, 2025February 2025 monthly summary for google/perfetto: Delivered targeted enhancements across PerfettoSQL, UI rendering, timing accuracy, and trace data exposure, delivering measurable improvements in data quality, developer velocity, and user experience. Focused on code quality, reliability, and performance to support scalable trace analysis and robust visualization at scale.
20 Commits • 4 Features
Feb 1, 2025February 2025 monthly summary for google/perfetto: Delivered targeted enhancements across PerfettoSQL, UI rendering, timing accuracy, and trace data exposure, delivering measurable improvements in data quality, developer velocity, and user experience. Focused on code quality, reliability, and performance to support scalable trace analysis and robust visualization at scale.
February 2025
January 2025
56 Commits • 20 Features
Jan 1, 2025January 2025 focused on stabilizing the Perfetto UI/engine experience while aggressively tidying the core TraceProcessor (TP) surface and accelerating large-trace analysis. Key UI work delivered consistent controls for the Trace Processor UI, resolved visualization gaps (thread names, tagging), and fixed flamegraph filtering crashes, enabling more reliable ad-hoc analysis. Core TP work cleaned up API and data paths, modernized frame/graphics parsing, and reduced maintenance burden. Performance initiatives introduced a new summarization path for v2 metrics, sped up large-trace queries, and prepared the ground for deeper visibility via metatrace. Release and build hygiene improved with canary rollout controls, versioning improvements, and GN/Bazel-related build stability.
January 2025
56 Commits • 20 Features
Jan 1, 2025January 2025 focused on stabilizing the Perfetto UI/engine experience while aggressively tidying the core TraceProcessor (TP) surface and accelerating large-trace analysis. Key UI work delivered consistent controls for the Trace Processor UI, resolved visualization gaps (thread names, tagging), and fixed flamegraph filtering crashes, enabling more reliable ad-hoc analysis. Core TP work cleaned up API and data paths, modernized frame/graphics parsing, and reduced maintenance burden. Performance initiatives introduced a new summarization path for v2 metrics, sped up large-trace queries, and prepared the ground for deeper visibility via metatrace. Release and build hygiene improved with canary rollout controls, versioning improvements, and GN/Bazel-related build stability.
December 2024
48 Commits • 10 Features
Dec 1, 2024December 2024 (2024-12) monthly summary for google/perfetto. Key achievements are centered on migrating the core Track System to a unified, scalable model, stabilizing the UI, and delivering data-path improvements that enable broader platform support and faster insights for performance analysis.
48 Commits • 10 Features
Dec 1, 2024December 2024 (2024-12) monthly summary for google/perfetto. Key achievements are centered on migrating the core Track System to a unified, scalable model, stabilizing the UI, and delivering data-path improvements that enable broader platform support and faster insights for performance analysis.
December 2024
November 2024
62 Commits • 18 Features
Nov 1, 2024Monthly Summary for 2024-11 (google/perfetto): This month focused on delivering UI enhancements, stability fixes, and backend refactors that improve usability, reliability, and data analysis capabilities. Key work spanned UI area selection, viewport caching, flamegraph and details panel state management, and track/pinned-tracks workflows, complemented by TP (Telemetry/Profiling) system improvements and track interning migrations.
November 2024
62 Commits • 18 Features
Nov 1, 2024Monthly Summary for 2024-11 (google/perfetto): This month focused on delivering UI enhancements, stability fixes, and backend refactors that improve usability, reliability, and data analysis capabilities. Key work spanned UI area selection, viewport caching, flamegraph and details panel state management, and track/pinned-tracks workflows, complemented by TP (Telemetry/Profiling) system improvements and track interning migrations.
October 2024
11 Commits • 4 Features
Oct 1, 2024October 2024 monthly summary focusing on key technical and business outcomes for google/perfetto, highlighting delivered features, major bug fixes, impact, and skills demonstrated.
11 Commits • 4 Features
Oct 1, 2024October 2024 monthly summary focusing on key technical and business outcomes for google/perfetto, highlighting delivered features, major bug fixes, impact, and skills demonstrated.
October 2024
Activity
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Quality Metrics
Correctness91.6%
Maintainability89.8%
Architecture88.0%
Performance84.2%
AI Usage20.6%
Skills & Technologies
Programming Languages
AconfigBPBUILDBashBazelBlueprintBzlCC++CSS
Technical Skills
AI IntegrationAPI DesignAPI DevelopmentAPI IntegrationAPI MigrationAlgorithm AnalysisAlgorithm DesignAlgorithm ImplementationAlgorithm OptimizationAlgorithm RefactoringAlgorithmsAndroid Build SystemAndroid DebuggingAndroid DevelopmentAutomation
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