The circonusllhist repository is a Go implementation of OpenHistogram's log-linear histogram data structure, providing a composable way to track histograms with reasoned accuracy bounds. The package, named circllhist, ports the functionality of the original C library libcircllhist into Go, enabling developers to work with fixed log-linear histograms in Go applications. The repository is maintained under the Apache 2.0 license and is part of the broader OpenHistogram project ecosystem.
The core purpose of this library is to offer an efficient data structure for histogram tracking that can be composed and aggregated while maintaining predictable error characteristics. Log-linear histograms are particularly valuable in performance monitoring and observability contexts where accurate latency and metric tracking is essential. The library's design allows for accurate reasoning about error bounds when working with histogram data, making it suitable for distributed systems and time-series applications where precision matters.
A key feature of the implementation is the use of bi-level sparse lookup tables, which improve insertion time by approximately twenty percent compared to implementations without these tables. However, this performance optimization comes with a memory cost, with lookup tables ranging from a minimum of roughly half a kilobyte to a maximum of approximately one hundred thirty kilobytes. The repository acknowledges this tradeoff and provides flexibility for users to opt out of lookup tables entirely when memory efficiency is prioritized over insertion speed. This is particularly relevant for applications managing large numbers of individual histograms where cumulative memory overhead becomes significant.
The library provides comprehensive documentation through both godoc and pkg.go.dev, ensuring developers have access to detailed API information. The usage examples in the repository demonstrate both standard histogram creation and advanced scenarios involving serialization and deserialization. For applications choosing to operate without lookup tables, the library offers careful guidance on correct serialization and deserialization practices to avoid excess memory allocation.
The repository supports both manual and implicit serialization approaches. Manual serialization allows developers to maintain tight control over memory usage when working with histograms without lookup tables. For implicit JSON serialization using Go's standard library, the repository provides a HistogramWithoutLookups wrapper that ensures no excess memory allocations occur during the deserialization process. Once deserialization is complete, the underlying histogram can be extracted using either the Histogram method or the HistogramWithLookups method, depending on whether lookup tables should be allocated.
GitGenius activity data indicates this repository maintains connections with significant projects including CockroachDB, the Go language repository itself, and OpenSearch, suggesting its relevance to high-performance distributed systems and observability infrastructure. The repository is tagged with the hacktoberfest topic, indicating openness to community contributions. The classification data reflects the library's positioning across multiple domains including histogram processing, performance analysis, latency tracking, metrics collection, and observability, confirming its role as a foundational component for systems requiring sophisticated statistical data aggregation and performance monitoring capabilities.