fjall Storage Engine Guide

fjall is the embedded LSM-tree storage engine that powers ECSdb. This guide covers its API and best practices.

fjall Overview

fjall is a pure Rust LSM-tree (Log-Structured Merge-tree) storage engine. It provides:

• Write-Ahead Log (WAL) for durability
• MemTable (skip list) for in-memory buffering
• SSTables (Sorted String Tables) for on-disk storage
• Background compaction
• Snapshots for consistent reads
• Partitions (our "column families")

Core Concepts