google/perfetto
Jan 2025 – Mar 2025
3 Months active
Languages Used
C++GNPythonSQLTypeScriptprotobuf
Technical Skills
Build System ConfigurationC++Data AggregationData VisualizationDatabase InternalsDebugging
Leszek Swirski
PROFILE
Leszek Swirski
Leszek worked on the google/perfetto repository, delivering cross-platform profiling enhancements and improving performance analysis workflows. He implemented Apple Instruments profiling support and integrated it into the UI, enhancing JIT symbolization and frame name handling using C++ and Protocol Buffers. Leszek enriched JavaScript trace data by adding line and column information to V8 function locations and aligning JS pprof frame formatting with native flamegraphs, improving cross-language observability. He also stabilized XML parsing for large files by introducing chunked parsing and allocation retry logic. His work demonstrated depth in system programming, data visualization, and performance profiling, addressing both feature development and robustness.
Overall Statistics
Feature vs Bugs
80%Features
Repository Contributions
8Total
Bugs
1
Commits
8
Features
4
Lines of code
1,137
Activity Months3
Your Network
4376 people
Work History
March 2025
1 Commits
Mar 1, 2025Concise monthly summary for 2025-03 focusing on the google/perfetto repository. Delivered stability improvements for the XML parser when processing very large XML inputs by implementing chunked parsing and allocation retry logic to prevent crashes and errors in high-volume ingestion scenarios.
1 Commits
Mar 1, 2025Concise monthly summary for 2025-03 focusing on the google/perfetto repository. Delivered stability improvements for the XML parser when processing very large XML inputs by implementing chunked parsing and allocation retry logic to prevent crashes and errors in high-volume ingestion scenarios.
March 2025
February 2025
1 Commits • 1 Features
Feb 1, 2025February 2025 performance month for google/perfetto focused on improving cross-language flamegraph consistency by aligning JavaScript pprof frame formatting with native flamegraphs. Implemented port of the frame naming logic from native flamegraph queries to the pprof exporter (currently via manual table lookups) and documented a TODO to unify with the SQL-based implementation. This work enhances observability and reduces context switching when analyzing performance across JS and native code.
February 2025
1 Commits • 1 Features
Feb 1, 2025February 2025 performance month for google/perfetto focused on improving cross-language flamegraph consistency by aligning JavaScript pprof frame formatting with native flamegraphs. Implemented port of the frame naming logic from native flamegraph queries to the pprof exporter (currently via manual table lookups) and documented a TODO to unify with the SQL-based implementation. This work enhances observability and reduces context switching when analyzing performance across JS and native code.
January 2025
6 Commits • 3 Features
Jan 1, 2025January 2025 monthly summary for Perfetto focused on delivering cross-platform profiling enhancements, richer JavaScript trace data, and data-flexible processing to drive faster performance analysis and better decision-making.
6 Commits • 3 Features
Jan 1, 2025January 2025 monthly summary for Perfetto focused on delivering cross-platform profiling enhancements, richer JavaScript trace data, and data-flexible processing to drive faster performance analysis and better decision-making.
January 2025
Activity
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Quality Metrics
Correctness91.4%
Maintainability85.0%
Architecture86.2%
Performance78.8%
AI Usage20.0%
Skills & Technologies
Programming Languages
C++GNPythonSQLTypeScriptprotobuf
Technical Skills
Build System ConfigurationC++Code RefactoringData AggregationData ExportData VisualizationDatabase InternalsDebuggingError HandlingJIT SymbolizationPerformance AnalysisPerformance OptimizationPerformance ProfilingProtocol BuffersSQL
Repositories Contributed To
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