plain-cache

Overview

plain-cache is a high-performance, thread-safe cache implementation that makes no use of unsafe Rust code. It implements the S3-FIFO eviction algorithm [see]. plain-cache allocates its capacity at cache instantiation time and is designed for high-throughput scenarios with minimal contention.

Key Features

• S3-FIFO eviction: Optimal cache performance with predictable behavior
• Sharded design: Reduces lock contention for concurrent access
• Built-in metrics: Track hits, misses, evictions, and timing
• Custom hashing: Support for different hash functions
• Memory pre-allocation: Fixed capacity allocated at creation time
• API simplicity: Straightforward get/insert interface

Quick Start

use plain_cache::Cache;

let cache = Cache::with_capacity(1000);
cache.insert("key", "value");
assert_eq!(cache.get("key"), Some("value"));

Use if you need

• High performance
• Thread safety
• No usage of unsafe code
• No background threads
• Cache metrics
• Small dependency tree
• Easy-to-reason cache eviction (S3-FIFO)
• Ability to provide custom hasher

Do not use if you need

• Zero-sized types
• Lifecycle hooks
• Item weighing
• Custom eviction policies
• Time-based eviction
• Explicit cache deletions
• Memory-based capacity limits
• Cache warming strategies