Cassandra Anti-Patterns: Queues and Queue-like Datasets | Datastax

Cassandra uses a log-structured storage engine, which employs tombstones to indicate deleted rows or columns. These tombstones are kept for at least the time specified by gc_grace_seconds before being discarded during compaction. While this system allows fast deletes and writes, it can lead to performance issues when reading data with many tombstones, especially in column-level deletes scenarios. To mitigate these issues, consider partitioning data with high churn rate into separate rows or tables and deleting entire rows or truncating tables when needed. Additionally, specifying a start column for queries can help skip collecting irrelevant tombstones and improve performance.