What is the fundamental difference between LSM-trees and B-trees?
B-trees store data in a sorted tree and seek the correct position on disk for every write, causing random I/O that bottlenecks under load. LSM-trees buffer writes in memory, then flush sorted blocks sequentially to disk, converting random writes into sequential I/O that enables millions of writes per second.
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LSM-Trees vs B-Trees: Why Cassandra Chose Sequential WritesB-trees seek random disk positions. LSM-trees buffer in memory and flush sequentially, converting random I/O into sequential writes for millions of ops/sec.
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