What is xxHash (XXH64)?
xxHash is an extremely fast non-cryptographic hash algorithm that focuses on speed and performance while maintaining good distribution properties. XXH64 is the 64-bit variant that produces a 64-bit (8-byte) hash value, typically displayed as a 16-character hexadecimal number.
Key characteristics:
- Extremely fast: Optimized for speed, much faster than cryptographic hash functions
- Deterministic: The same input always produces the same hash
- Good distribution: Provides excellent hash distribution for hash tables
- Non-cryptographic: Not suitable for security purposes, designed for performance
- Larger output: 64-bit hash provides better collision resistance than 32-bit variants
- Platform optimized: Uses SIMD instructions when available for maximum speed
Common uses:
- Hash tables and data structures
- File integrity checks (non-security)
- Data deduplication
- Checksums for data transmission
- Performance-critical applications
- Database indexing
- Cache keys generation