Tag
compaction
- Aug 20, 2026 Deletes, Tombstones, and the Append-Only Sink Object storage cannot delete a row in place, so removal becomes a recorded fact with a retention period, and every reader must agree on how to apply it. data engineering
- Jul 17, 2026 Quantile Summaries: Greenwald-Khanna Bounds and the KLL Compactor How a deterministic summary tracks ranks within a guaranteed error using tuple invariants, and how randomised compaction reaches constant space per item with a smaller constant. algorithms
- Jun 5, 2026 Erasing From the Middle: Compaction and the Order It Destroys Why removal from a contiguous array costs a shift, when swap-and-pop is the right substitute, and how tombstone markers defer the cost without hiding it. data structures
- May 14, 2026 Keeping a Vector Index Current Without Rebuilding It How segments, tombstones, and compaction let an index absorb edits, why deletion is more expensive than insertion, and where the visible-lag window comes from. inference systems
- May 8, 2026 Leveled Compaction and the Shape of the LSM Tree Why leveled compaction keeps each level ten times the size of the one above, what that costs in write amplification, and how tiering trades it back. databases
- Nov 17, 2025 Tombstones, Merges, and the Cost of Keeping a Vector Index Current Why deleting from a proximity graph is harder than inserting, how segment-and-merge maintenance bounds the damage, and when a rebuild is cheaper than incremental repair. information retrieval
- Oct 16, 2025 LSM Compaction: Size-Tiered and Leveled Strategies Compared How an LSM tree turns random writes into sequential ones, what each compaction strategy costs in read amplification and space amplification, and when the write stalls arrive. databases
- Aug 19, 2024 Small File Accumulation and What Compaction Must Preserve Why frequent small commits degrade a table long after the commits stop, how a compaction job rewrites files without breaking snapshots, and which invariants it cannot violate. data engineering
- Mar 14, 2023 Mark-Compact: Sliding Objects Without a Second Semispace How a compacting collector relocates live objects into one end of the same heap, the two passes needed to compute and then apply new addresses, and why the ordering of objects matters. language runtimes