Topic 2 — notes

Predictions (fill BEFORE running benches)

Reading answers

redis dict (reading-redis-dict.md)

1. Insert into ht[0] during rehash — why a bug:
2. pauserehash exists for:
3. empty_visits=10n tail guarantee:

redis skiplist (reading-redis-skiplist.md)

1. Why skiplist + dict both:
2. Expected search cost at p=0.25, priced vs measured:

hashbrown (reading-hashbrown.md)

1. 7/8 vs 1.0 load factor:
2. Hash policy paragraph (for M2 decision):
3. DELETED churn ↔ LSM tombstones:

RocksDB memtable (reading-rocksdb-memtable.md)

1. spans/backward under concurrent CAS:
2. acquire/release vs SeqCst at line 383:
3. Miss estimate vs hashbrown number:

rax / ART / SwissTable talk

• (questions in each guide)

Experiment findings

• rehash_spike table + per-decile max:
• Where my skiplist loses to hashbrown and by how much (RUM terms):
• Implementation trade I chose for skiplist node layout, and why:

M2 log

• attribute-store design written BEFORE peeking at reference
• comparison vs reference attribute_store.rs / string_pool.rs:
• hash policy decision + bench evidence: