February 2026 monthly summary for GreptimeTeam/greptimedb focused on delivering throughput, test efficiency, and PromQL compatibility improvements, with robust regression coverage to guard against regressions. Key contributions spanning performance, reliability, and compatibility: - Memtable Performance Optimization: reduces redundancy by merging last_non_null within memtable batches, increasing data handling throughput for heavy-write workloads. - Slow Query Threshold for Integration Tests: introduces a threshold to flag slow queries and optimizes the frontend test waiting mechanism, shortening feedback cycles and improving test monitoring. - PromQL Group By Support: enables aggregation by a single field with adjusted output types and regression tests, expanding PromQL expressiveness. - PromQL Filter Join RHS Column Dropping: fixes join correctness by dropping unnecessary RHS columns to avoid ambiguous references, with regression tests for vector-vector and scalar-vector scenarios. - Prometheus 3.x Compatibility Updates: adapts matrix selector and lookback semantics to Prometheus 3.x, aligning timestamp comparisons and expected results, supported by regression tests for compatibility. Overall impact: improved data throughput and reliability, faster development feedback loops, and stronger PromQL feature parity with Prometheus 3.x, enabling customers to build faster, more accurate dashboards and queries. Technologies/skills demonstrated: performance optimization, test automation and regression testing, feature derivation and validation for PromQL, compatibility adaptations for Prometheus upgrades, and end-to-end validation through regression suites.

January 2026 performance summary focusing on GreptimeDB and ClickBench deliverables. Key work spanned metadata visibility improvements, partition management, PromQL reliability, and query engine performance, complemented by benchmarking tooling and build-stability initiatives. These efforts enhanced data discoverability, scalability, and operational efficiency, while delivering more accurate results and reproducible benchmarks.

Monthly summary for GreptimeTeam/greptimedb - December 2025 Overview: Delivered a set of performance, reliability, and usability improvements across data processing, histogram/PromQL analytics, SQL query handling, partition evaluation, release automation, and developer experience. These initiatives collectively reduced latency, improved data accuracy, strengthened operational resilience, and enhanced collaboration practices. Key features delivered: - Data processing performance improvements: Removed DataFusion DataFrame wrapper to simplify data handling and introduced eager decoding of primary key values for faster data access. Business value: lower data access latency and improved query throughput. Commits: 9d35b8cad4df3f82324e57c2e0109d20edd01638; edb1f6086f62d99f588476af1142455303b71695. - Robust histogram and PromQL enhancements: Added safe mode for histogram quantile calculations, improved multi-partition histogram handling, and fixed/optimized PromQL histogram folding. Business value: more stable, accurate metrics under partial data conditions and across partitions. Commits: 60f752d3067e4b8118c1ed96da48c98398753842; cbfdeca64cd806a9179a2fd744dc24850aaa8cc0; bd3ad6091014d22c528706334b0a630627881954. - SQL query optimization improvements: Enhanced handling of DISTINCT in SQL queries by classifying commutativity and expanding test coverage. Business value: faster and more predictable query planning and execution. Commit: f2288a86b044ef868dd6dde6271a5de27d1ec369. - Partition sorting and evaluation improvements: Improved partition sorting behavior, termination conditions across partitions, and introduced sorting for SQLNESS histogram results. Business value: more efficient query planning and more consistent histogram results. Commits: 6817a376b5e7848e0dd78a9ea8c30e2e3d015c85; b6017816047c947b3815ae926a2224966233f7a2; e0697790e6c7676d1d08fc37110662e9f54f92be. - Nightly release process enhancements: Allow publishing nightly releases when some platforms are unavailable and unify Linux platform handling. Business value: faster release cycles with broader platform coverage and reduced release friction. Commit: 0ebfd161d844881c150396fdf5649191623a8611. - Documentation and test improvements: Added documentation comments to tables, columns, and flows; refactored window sort tests for better readability and coverage. Business value: improved maintainability, onboarding, and test reliability. Commits: 564cc0c750e1eb63c80ba8aae3972245cd47770c; ab426cbf897f7c8291f5319f32b349f89a8cdb1d. - Contributor guidelines for AI-assisted contributions: Introduce guidelines to guide AI-assisted contributions and emphasize code review and knowledge sharing. Business value: improved collaboration safety and code quality in AI-assisted workflows. Commit: 0cea58c642f209a5f7d7b32552f2038f03ecf8fa. Major bugs fixed: - PromQL histogram with aggregation fix (#7393) to ensure correct results on aggregated histograms. - PromQL offset direction fix (#7392) to ensure accurate time-aligned histogram calculations. - Part sort behavior fix (#7374) to stabilize sorting across partitions. - Part sort optimization for overlapping time windows (#7387) to improve performance in edge cases. Overall impact and accomplishments: - Performance: Data access latency reduced through direct PK decoding and removal of DataFusion wrapper, strengthening data processing latency and throughput. - Reliability and correctness: Histogram/PromQL enhancements and robust handling of incomplete data improve metric accuracy; partition sorting improvements stabilize executions across distributed data. - Release agility: Nightly release enhancements lowered blockers and increased deployment cadence across platforms. - Collaboration and quality: Documentation, tests, and AI-contribution guidelines improved onboarding, knowledge sharing, and code quality. Technologies/skills demonstrated: - Data engineering: DataFusion wrapper removal, eager primary key decoding, data processing optimization. - Metrics and analytics: Histogram quantiles, PromQL improvements, histogram folding. - SQL engineering: DISTINCT commutativity classification, test coverage expansion. - Systems and release engineering: Nightly release workflow, cross-platform release handling. - Developer experience: Documentation, tests, and AI-assisted contribution guidelines. This work establishes a stronger foundation for scalable analytics and faster iteration through improved data handling, metrics reliability, and streamlined release processes.

November 2025 highlights: Delivered cross-repo improvements that boost data integrity, performance, and observability for Greptime DB and Proto. Key features include partition management inheritance with validation, dynamic tracing controls and metrics reporting, merge-scan/query performance improvements, dictionary data type support with proto extension, and a targeted deadlock fix in the metric engine. These initiatives reduce data integrity risk, speed up queries, and broaden data format capabilities while improving reliability under concurrent workloads.

For 2025-10, delivered the Partitioning and Repartition Framework in Greptimedb, enabling unified partitioning, repartitioning, and partition-aware querying. Implemented a new partition subtasks module, SST remapping on partition changes, application of partition expressions during region scans, and parser support for ALTER TABLE ... REPARTITION to enable future repartitioning workflows. This work enhances data organization, query performance, and future-proofing of partitioning operations. Commits focused on implementing the new framework and related capabilities (e.g. e46ce7c6daf3093d0ee0793f31e5356be4b733ca, ab461274143f0ee3054f87ef91859c544be917a5, 1a73b485fe16c9500af1c9aa05f22ae61a2b41c6, aa98033e8572dfb54cdc2aa97ea855291c97e723).

September 2025 performance highlights across spiceai/datafusion and GreptimeDB focused on maintainability, performance, and correctness. Key features were delivered to simplify data workflows and improve observability, while critical correctness fixes reduced risk in queries and data processing. The month also emphasized build and environment improvements to support stability and faster onboarding.

Concise monthly summary for August 2025 focusing on key features delivered, major bug fixes, overall impact, and technologies demonstrated across GreptimeDB and related repos.

July 2025 monthly summary focused on delivering robust data workflows, improving correctness of partitioning, and advancing observability and parser capabilities across GreptimeDB, Arrow-RS, and DataFusion. Key business/value outcomes: - Strengthened data pipeline correctness and safety (prevents misconfigured data flows and ensures reliable data routing). - Improved data governance and operational observability with enhanced metrics and standardized file references. - Expanded SQL/TQL compatibility and planning capabilities for more flexible query construction and optimization. - Documented methodology for repartitioning to guide future migrations with safety checks.

June 2025 performance summary focused on correctness, observability, and query expressiveness across core data platforms, delivering business value through accurate analytics, reliable data handling, and improved automation/diagnostics. Key progress included targeted fixes to ensure logical tables operate with correct partition behavior, enhancements to PromQL capabilities for more expressive queries, and richer, machine-friendly explain/analyze outputs.

May 2025 highlights: Delivered stability, performance, and usability improvements across the GreptimeDB stack, focusing on PromQL reliability, query planning efficiency, data ingestion ergonomics, and scalable write paths. Business value includes faster dashboards and alerts, more reliable data processing, and improved developer productivity across multiple repos.

April 2025 monthly summary: Delivered impactful enhancements across the Greptime organization, with a focus on PromQL performance, reliability, and developer experience, plus proto-level feature delivery and documentation improvements. Key achievements span across three repositories: proto, DB server, and docs, delivering more flexible data normalization, faster and more reliable query execution, API refinements, enhanced observability, and clearer user guidance.

March 2025 monthly summary focusing on delivering expressive analytics, robust planning, and improved observability across core data processing and storage components. Key cross-repo work includes feature-rich query capabilities, distribution-aware scanning, and codebase stability improvements that support the 0.14.0 release.

February 2025 performance and feature highlights across GreptimeDB, Greptime-Proto, and Docs. Delivered notable performance improvements, architecture refactors, and protocol/PromQL enhancements that drive throughput, reliability, and developer experience.

January 2025 performance summary for GreptimeTeam repositories. Focused on delivering high-value features, stabilizing data pipelines, and improving observability and performance. Key outcomes include enhanced Grafana dashboards for new metrics, deeper flownode observability, and a safer, faster ingestion and query pathway.

December 2024 monthly summary focused on delivering feature-rich, observable, and reliable improvements across docs, greptimedb, and opendal, while hardening security and correctness. The work emphasizes business value through improved discoverability, advanced query capabilities, efficient data access paths, and robust metrics and monitoring. Key accomplishments include delivering new user-facing features with broad impact, upgrading core infrastructure integrations, and completing important code cleanup and hardening tasks to reduce debt and improve maintainability.

November 2024 performance highlights across core data platforms, delivering faster query responses, more robust metadata handling, and enhanced ETL/data processing pipelines. Key work spanned GreptimeDB, SpiceAI DataFusion, and Apache Arrow Rust, focusing on feature delivery, stability, and CI/compliance improvements to boost reliability, efficiency, and developer velocity.

2024-10 GreptimeDB Monthly Summary Key features delivered: - Configuration Examples Clarification and Correct Formatting: Updated example TOML configuration files to correctly format the tracing section headers and ensure the [tracing] header is properly commented out, improving user guidance and preventing misconfigurations. - Windowed-sort Optimizer Enhancements: Enhanced the windowed-sort optimizer rule by adding metadata to RegionScanners, optimizing PartSort execution, skipping PartSort when there is no tag column, and ensuring correct handling of descending order for accurate results. Major bugs fixed: - Resolved configuration example formatting issues that could mislead users; specifically updated tracing section headers in the example TOML files to conform to expected syntax (#4898). Overall impact and accomplishments: - Improved query performance and reliability for sorting-heavy workloads, leading to faster dashboards and analytics. - Reduced user support friction by providing clearer configuration examples and more robust optimizer behavior. Technologies/skills demonstrated: - Optimizer engineering (windowed-sort), metadata usage, and performance-oriented code changes. - TOML configuration handling and user-facing documentation fixes. - Code quality, maintainability, and bug-fix discipline in config management. Repo: GreptimeTeam/greptimedb Month: 2024-10