Module file_io 

File I/O service adapter

File I/O Service Implementation

This module is part of the Infrastructure layer, providing concrete implementations of domain interfaces (ports).

This module provides the concrete implementation of the file I/O service interface for the adaptive pipeline system. It offers high-performance file operations with memory mapping support, asynchronous I/O, and comprehensive error handling.

Overview

The file I/O service implementation provides:

• Memory Mapping: High-performance file access using memory-mapped files
• Asynchronous I/O: Non-blocking file operations using Tokio
• Chunked Processing: Efficient processing of large files in chunks
• Statistics Tracking: Comprehensive I/O performance metrics
• Error Handling: Robust error handling and recovery

Architecture

The implementation follows the infrastructure layer patterns:

• Service Implementation: TokioFileIO implements domain interface
• Memory Management: Efficient memory usage with memory mapping
• Concurrency: Thread-safe operations with parking_lot RwLock
• Configuration: Flexible configuration for different use cases

Performance Features

Memory Mapping

Uses memory-mapped files for optimal performance:

• Zero-Copy: Direct memory access without copying data
• OS Optimization: Leverages operating system virtual memory
• Cache Efficiency: Better CPU cache utilization
• Large File Support: Efficient handling of multi-gigabyte files

Asynchronous Operations

All I/O operations are asynchronous:

• Non-Blocking: Doesn’t block the async runtime
• Concurrent Processing: Multiple files can be processed simultaneously
• Resource Efficiency: Optimal use of system resources
• Scalability: Handles high concurrent load

Chunked Processing

Processes files in configurable chunks:

• Memory Efficiency: Constant memory usage regardless of file size
• Progress Tracking: Real-time progress monitoring
• Error Recovery: Granular error handling per chunk
• Parallel Processing: Chunks can be processed in parallel

Configuration Options

The service supports various configuration options:

Buffer Sizes

• Read Buffer: Configurable read buffer size
• Write Buffer: Configurable write buffer size
• Chunk Size: Optimal chunk size for processing

Memory Mapping

• Threshold: Minimum file size for memory mapping
• Alignment: Memory alignment for optimal performance
• Prefetch: Prefetch strategies for sequential access

Concurrency

• Thread Pool: Configurable thread pool size
• Concurrent Reads: Maximum concurrent read operations
• Concurrent Writes: Maximum concurrent write operations

Usage Examples

Basic File Reading

Chunked File Processing

Error Handling

Comprehensive error handling for:

• File System Errors: Permission denied, file not found, etc.
• I/O Errors: Read/write failures, disk full, etc.
• Memory Mapping Errors: Mapping failures, access violations
• Configuration Errors: Invalid parameters, resource limits

Performance Characteristics

Throughput

• High Bandwidth: Optimized for maximum I/O throughput
• Low Latency: Minimal overhead for small operations
• Scalable: Performance scales with available system resources

Memory Usage

• Efficient: Minimal memory overhead
• Predictable: Constant memory usage for chunked processing
• Configurable: Tunable memory usage based on requirements

Thread Safety

The implementation is fully thread-safe:

• Concurrent Access: Multiple threads can use the service simultaneously
• Lock-Free Reads: Read operations don’t block each other
• Atomic Updates: Statistics and configuration updates are atomic

Integration

The service integrates with:

• Domain Layer: Implements FileIOService trait
• Processing Pipeline: Provides file access for pipeline stages
• Metrics System: Reports detailed I/O performance metrics
• Configuration System: Dynamic configuration updates

Structs

TokioFileIO

Implementation of FileIOService with memory mapping support