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Databases

2 posts tagged Databases.

HNSW: What the Vector Similarity Search Paper Actually Says

Every vector database runs HNSW under the hood. Most engineers tune M and ef_construction without understanding what they're actually trading off. The paper rewards a close read.

Cassandra: What the Paper Actually Says

We had a Cassandra cluster where DELETE operations made reads progressively slower until queries timed out. Adding more disk space made it worse. The root cause is described precisely in the 2009 paper — but only if you understand that Cassandra cannot actually delete data.