Scaling Writes hard
In the context of database storage engines on SSDs, what causes 'Write Amplification'?
- A Writing to logs.
- B Network duplication.
- C Replication.
- D The mismatch between database Page Size (e.g., 16KB) and SSD Erase Block Size (e.g., 4MB). To update a small page, the SSD must read, merge, and rewrite a massive block.
Answer: D. The mismatch between database Page Size (e.g., 16KB) and SSD Erase Block Size (e.g., 4MB). To update a small page, the SSD must read, merge, and rewrite a massive block.
SSDs cannot overwrite data in place; they must erase a whole block. Small random database writes trigger massive internal SSD maintenance, reducing throughput and disk lifespan.
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