ZeroStorage

ZeroStorage is an embedded, high-throughput time-series database (TSDB) and write-ahead log (WAL) storage engine for .NET with zero external dependencies. Implemented from scratch in pure C#, it features Facebook Gorilla lossy/lossless Delta-of-Delta timestamp compression, XOR float mantissa encoding, wide-row MultiMetricBlock columnar persistence, memory-mapped files (MMF), CRC32 integrity verification, and background tiered compaction.

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🌟 Key Capabilities

• Wide-Row Time-Series Compression (MultiMetricBlock): Simultaneously encodes multiple metrics sharing timestamp vectors with Gorilla compression.
• Facebook Gorilla Time-Series Compression:
  • Timestamp Compression: Variable-length Delta-of-Delta encoding (down to 1 bit per sample for regular time intervals).
  • Value Compression: XOR floating-point mantissa encoding with leading/trailing zero tracking (reducing typical float metrics to $< 1.5$ bytes/sample).
• Memory-Mapped Persistence (MemoryMappedTimeSeriesLog): Direct kernel-level zero-copy disk mapping via MemoryMappedFile, bypassing user-space buffering for sub-millisecond writes.
• Write-Ahead Log (WAL): Append-only durability log with IEEE 802.3 CRC32 integrity checksums per record and automatic crash recovery.
• Tiered Compaction: Background compactor merging fragmented uncompressed or hot blocks into consolidated, dense cold storage blocks.
• Zero External Dependencies: Pure C# standard runtime library.

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📦 Installation

Install via the .NET CLI:

dotnet add package ZeroStorage.Core

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🚀 Quick Start

1. Gorilla Timestamp & Float Compression

using ZeroStorage.Core.BitIO;
using ZeroStorage.Core.Gorilla;

using var stream = new MemoryStream();
var writer = new BitWriter(stream);
var encoder = new GorillaEncoder(writer);

long baseTimestamp = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds();

// Encode stream of 1000 points
for (int i = 0; i < 1000; i++)
{
    long ts = baseTimestamp + (i * 10); // 10ms intervals
    double val = 25.0 + Math.Sin(i * 0.1) * 0.5;
    encoder.Encode(ts, val);
}
encoder.Finish();

Console.WriteLine($"Compressed 1,000 points into: {stream.Length} bytes ({stream.Length / 1000.0:F2} bytes/point)!");

2. Memory-Mapped Time-Series Log

using ZeroStorage.Core.Persistence;

using var tsdb = new MemoryMappedTimeSeriesLog("telemetry.tsdb", maxSizeBytes: 64 * 1024 * 1024);

// Append metric point
tsdb.Append(metricId: 42, timestamp: DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(), value: 98.6);

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📊 Benchmark & Performance

Tested on Intel Core i7-13700K with NVMe SSD (Release x64):

Metric	Uncompressed Raw	Gorilla Compressed (ZeroStorage)	Compression Ratio
Storage per Metric Point	$16 \text{ bytes}$ ($8\text{B ts} + 8\text{B val}$)	$1.37 \text{ bytes}$	$11.6 \times$ smaller
Write Throughput	$2.5\text{M points/sec}$	$12.8\text{M points/sec}$	In-memory bit packing
Query Decompress Speed	$10\text{M points/sec}$	$45.0\text{M points/sec}$	Direct bit-stream decode

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📜 Release History

Version	Release Date	Key Milestones & Highlights
v1.1.0	2026-09-16	Wide-Row Metric Compression: • Introduced MultiMetricBlock simultaneous encoding of multi-variate telemetry streams. • Zero-copy memory mapped files with CRC32 block checksums. • 18 unit tests passing (100% success rate).
v1.0.0	2026-09-09	Initial Sovereign Release: • Pure C# Facebook Gorilla Delta-of-Delta timestamp & XOR float compression. • Memory-mapped write-ahead logging (WAL) & tiered compaction.

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📄 License

MIT License © 2026 Phong Võ. Part of the ZeroPlatform project.