Determine Whether Two Files Are Identical at Scale
Context
Design a robust and scalable method to determine if two files are bitwise identical. The files can be very large and may be located across different directories or machines. The solution must minimize CPU, memory, I/O, and network costs, ensure negligible collision risk, and support a deduplication workflow.
Requirements
Describe a step-by-step approach that addresses the following:
- Hashing Algorithm Choice: Discuss the selection of hashing algorithms (e.g., MD5 vs SHA-256) and provide a clear rationale for your choice.
- Collision Mitigation: Explain strategies to mitigate collision risk and define when it's appropriate to fall back to a byte-by-byte verification.
- Large File Efficiency: Detail methods for efficiently streaming and hashing very large files.
- Metadata Pre-checks: Identify what metadata (e.g., size, modification time) you would check before initiating any hashing process.
- Deduplication Workflow Integration: Describe how this file comparison mechanism would integrate into a broader deduplication workflow, especially when files are spread across different directories or machines.
AI interview prep
Core dilemma
Balancing the absolute correctness required for bitwise file identity with the performance and resource constraints of comparing potentially massive files across a distributed system.
3 tradeoffs and 3 stress tests locked
Interview prep
Unlock the interviewer X-Ray rubric, tradeoff matrix, stress tests, clarifying questions, and key concepts.
Determine Whether Two Files Are Identical at Scale
Context
Design a robust and scalable method to determine if two files are bitwise identical. The files can be very large and may be located across different directories or machines. The solution must minimize CPU, memory, I/O, and network costs, ensure negligible collision risk, and support a deduplication workflow.
Requirements
Describe a step-by-step approach that addresses the following:
- Hashing Algorithm Choice: Discuss the selection of hashing algorithms (e.g., MD5 vs SHA-256) and provide a clear rationale for your choice.
- Collision Mitigation: Explain strategies to mitigate collision risk and define when it's appropriate to fall back to a byte-by-byte verification.
- Large File Efficiency: Detail methods for efficiently streaming and hashing very large files.
- Metadata Pre-checks: Identify what metadata (e.g., size, modification time) you would check before initiating any hashing process.
- Deduplication Workflow Integration: Describe how this file comparison mechanism would integrate into a broader deduplication workflow, especially when files are spread across different directories or machines.