SYSTEMS NOTE № 42
The fastest query is the one your storage layout already understands.
A field guide to partitioning, pruning, and measuring the work a query engine never had to do.
EXECUTION
Reading an explain plan without reading tea leaves
Begin with cardinality and exchanged bytes. The impressive operator names can wait.
Open note →STORAGE
Small files are a scheduling problem in disguise
Compaction changes more than throughput: it changes the shape of planning work.
Open note →METHOD
A benchmark should leave an audit trail
Hardware, warm-up, data shape, and failure counts belong beside the headline number.
Open note →BENCH DESK
Record the conditions, not just the winner.
Reproducible performance work starts with a visible contract: fixed data, disclosed concurrency, separate warm and cold runs, and enough repetitions to expose the tail.
| Run | Cache | Rows | P95 |
|---|---|---|---|
| A-17 | cold | 84.2m | 1.82s |
| A-18 | warm | 84.2m | 0.41s |
| A-19 | warm | 84.2m | 0.43s |