Introduction to External Memory Algorithms
The need for external memory considerations.
Overview of the memory hierarchy.
The I/O Model of Computation
Understanding I/O operations.
Measuring I/O efficiency.
File-Based Storage Systems
File systems and their roles.
File organization methods.
Sequential and Random Access
Access patterns and performance implications.
Hashed Files
Implementing hash functions in file storage.
Handling collisions in external storage.
Indexed Files
Purpose and types of file indexes.
Index structures.
B-Trees Introduction
Structure and why they're suitable for disk storage.
B-Trees Operations
Search, insertion, and deletion algorithms.
Balancing and node splitting.
B+ Trees
Differences from B-Trees.
Advantages in database indexing.
External Sorting Algorithms
Challenges of sorting large datasets.
External Merge Sort Techniques
Minimizing disk I/O.
Multi-way Merge Sort
Improving efficiency in external sorting.
Buffer Management Strategies
Caching and prefetching.
Minimizing disk I/O.
External Hashing Techniques
Extendible hashing.
Linear hashing.
File Allocation Methods
Contiguous, linked, and indexed allocation.
Trade-offs and performance.
Directory Structures in File Systems
Single-level vs. hierarchical directories.
File metadata management.
RAID Storage Technologies
RAID levels and configurations.
Balancing performance and redundancy.
Solid-State Drives (SSDs)
SSD characteristics.
Implications for algorithm design.
Database Storage Mechanisms
Tablespaces, extents, segments.
Indexing strategies in databases.
External Memory Data Structures
External priority queues.
External graph representations.
Performance Analysis of External Algorithms
I/O complexity models.
Trade-offs between computation and I/O.
Applications and Case Studies
Real-world systems utilizing external memory algorithms.
Emerging Storage Technologies
Cloud storage considerations.
Distributed file systems (e.g., HDFS).
Future Trends in Storage
Big Data challenges.
Persistent memory technologies.
External Memory in Big Data
MapReduce and external data processing.