apache/impala
Oct 2025 – Mar 2026
6 Months active
Languages Used
C++JavaPythonThriftXMLSQL
Technical Skills
API developmentBackend DevelopmentC++Database ManagementJavaPython
Arnab Karmakar
PROFILE
Arnab Karmakar
Arnab worked on the apache/impala repository, delivering thirteen features and resolving three bugs over six months. He focused on backend development and data engineering, building enhancements such as Iceberg metadata migration, advanced partition filtering, and improved catalog observability. Using C++, Java, and Python, Arnab implemented memory-efficient data structures, optimized query planning, and extended API compatibility for ODBC/JDBC drivers. His work included robust unit and integration testing, detailed logging for diagnostics, and web UI improvements for operational visibility. The depth of his contributions is reflected in careful validation, cross-language serialization, and thoughtful handling of edge cases across storage backends and query workflows.
Overall Statistics
Feature vs Bugs
81%Features
Repository Contributions
19Total
Bugs
3
Commits
19
Features
13
Lines of code
8,262
Activity Months6
Your Network
46 peopleShared Repositories
46
ttttttzMember
Abhishek RawatMember
Andrew ShermanMember
Balazs HeveleMember
Zoltan Borok-NagyMember
zhangyifan27Member
Csaba RinghoferMember
Daniel BeckerMember
Daniel BeckerMember
Work History
March 2026
2 Commits
Mar 1, 2026March 2026 monthly highlights for apache/impala: Implemented host statistics logging enhancements to support erasure-coded storage and environments without disk IDs, improving observability and reliability of host-level metrics. Key changes include tracking unique host indices separately from host:disk pairs, and conditionally logging host:disk pairs only when disk IDs are valid. This ensures host stats are present for EC blocks and non-disk-id storage like Ozone. Tests were updated to skip disk-ID validation in EC/Ozone scenarios. The changes were implemented in FileMetadataStats (uniqueHostIndices) and test_file_metadata_stats with IS_OZONE checks. All tests pass with EC and Ozone configurations, ensuring backward compatibility and improved confidence in host statistics across storage backends.
2 Commits
Mar 1, 2026March 2026 monthly highlights for apache/impala: Implemented host statistics logging enhancements to support erasure-coded storage and environments without disk IDs, improving observability and reliability of host-level metrics. Key changes include tracking unique host indices separately from host:disk pairs, and conditionally logging host:disk pairs only when disk IDs are valid. This ensures host stats are present for EC blocks and non-disk-id storage like Ozone. Tests were updated to skip disk-ID validation in EC/Ozone scenarios. The changes were implemented in FileMetadataStats (uniqueHostIndices) and test_file_metadata_stats with IS_OZONE checks. All tests pass with EC and Ozone configurations, ensuring backward compatibility and improved confidence in host statistics across storage backends.
March 2026
February 2026
4 Commits • 3 Features
Feb 1, 2026February 2026 monthly summary for apache/impala development focusing on performance, scalability and observability improvements. Key features delivered include significant Iceberg metadata and predicate pushdown enhancements, plus improved Catalogd observability. Major bugs fixed include memory and performance-related optimizations tied to Iceberg path hashing and LIKE predicate pushdowns. Overall impact includes a substantially smaller memory footprint for Iceberg file path hashes (~4x reduction), faster query planning and file-level pruning via Iceberg metadata, and better operational visibility through an enhanced Catalogd /operations page. Technologies and skills demonstrated span data structure design (THash128), Thrift and cross-language serialization (Hash128 Java class), performance-oriented migrations (Murmur3 to XXH128), C++ operator support, extensive testing (JUnit, iceberg-like-pushdown.test), and service observability enhancements.
February 2026
4 Commits • 3 Features
Feb 1, 2026February 2026 monthly summary for apache/impala development focusing on performance, scalability and observability improvements. Key features delivered include significant Iceberg metadata and predicate pushdown enhancements, plus improved Catalogd observability. Major bugs fixed include memory and performance-related optimizations tied to Iceberg path hashing and LIKE predicate pushdowns. Overall impact includes a substantially smaller memory footprint for Iceberg file path hashes (~4x reduction), faster query planning and file-level pruning via Iceberg metadata, and better operational visibility through an enhanced Catalogd /operations page. Technologies and skills demonstrated span data structure design (THash128), Thrift and cross-language serialization (Hash128 Java class), performance-oriented migrations (Murmur3 to XXH128), C++ operator support, extensive testing (JUnit, iceberg-like-pushdown.test), and service observability enhancements.
January 2026
3 Commits • 1 Features
Jan 1, 2026January 2026 monthly summary for apache/impala focused on reliability, observability, and correctness improvements across table loading and Iceberg integration. Key outcomes include enhanced diagnostics for file metadata during table loads, corrected partition transform validation, and increased test stability through a flaky test fix for table usage metrics.
3 Commits • 1 Features
Jan 1, 2026January 2026 monthly summary for apache/impala focused on reliability, observability, and correctness improvements across table loading and Iceberg integration. Key outcomes include enhanced diagnostics for file metadata during table loads, corrected partition transform validation, and increased test stability through a flaky test fix for table usage metrics.
January 2026
December 2025
4 Commits • 4 Features
Dec 1, 2025December 2025 monthly summary focusing on Iceberg integration, partition visibility, and catalog observability for Impala. Delivered metadata-only migration from non-Iceberg HDFS sources to Iceberg, enhanced partition filtering and management, added catalog load metrics, and exposed HDFS partition metadata via WebUI, driving business value through migration readiness, visibility, and operational telemetry.
December 2025
4 Commits • 4 Features
Dec 1, 2025December 2025 monthly summary focusing on Iceberg integration, partition visibility, and catalog observability for Impala. Delivered metadata-only migration from non-Iceberg HDFS sources to Iceberg, enhanced partition filtering and management, added catalog load metrics, and exposed HDFS partition metadata via WebUI, driving business value through migration readiness, visibility, and operational telemetry.
November 2025
2 Commits • 2 Features
Nov 1, 2025Month: 2025-11 — Delivered two core features that enhance developer tooling, diagnostics, and log readability for apache/impala, with strong test coverage and engineering discipline. No major bugs fixed this period; emphasis on feature delivery, quality, and maintainability.
2 Commits • 2 Features
Nov 1, 2025Month: 2025-11 — Delivered two core features that enhance developer tooling, diagnostics, and log readability for apache/impala, with strong test coverage and engineering discipline. No major bugs fixed this period; emphasis on feature delivery, quality, and maintainability.
November 2025
October 2025
4 Commits • 3 Features
Oct 1, 2025Month: 2025-10 — This month delivered major feature work across HiveServer2, SHOW commands, and geospatial utilities, with a strong emphasis on improving compatibility, admin usability, and test coverage. Business value was enhanced through broader driver interoperability (ODBC/JDBC), easier recreation of tables and partitions, and parity with PostGIS for geospatial operations. Technologies demonstrated include C++ backend changes, Python-based test suites, and SQL parser/analyzer enhancements, all validated through CI-tested unit/integration tests.
October 2025
4 Commits • 3 Features
Oct 1, 2025Month: 2025-10 — This month delivered major feature work across HiveServer2, SHOW commands, and geospatial utilities, with a strong emphasis on improving compatibility, admin usability, and test coverage. Business value was enhanced through broader driver interoperability (ODBC/JDBC), easier recreation of tables and partitions, and parity with PostGIS for geospatial operations. Technologies demonstrated include C++ backend changes, Python-based test suites, and SQL parser/analyzer enhancements, all validated through CI-tested unit/integration tests.
Activity
Loading activity data...
Quality Metrics
Correctness99.0%
Maintainability84.2%
Architecture94.8%
Performance87.4%
AI Usage29.4%
Skills & Technologies
Programming Languages
C++JavaPythonSQLThriftXML
Technical Skills
API designAPI developmentBackend DevelopmentC++C++ developmentData EngineeringDatabase ManagementJavaPythonSQLback end developmentbackend developmentdata engineeringdata processingdata structures
Repositories Contributed To
Overview of all repositories you've contributed to across your timeline