NOTE
Ziplist (Historical Redis Structure)
Historical compact sequential Redis encoding and the general memory-versus-update-cost trade-off of packed representations.
This is a historical learning note and may contain outdated or incomplete understanding.
Redis historically used ziplist as a compact sequential encoding for small collections. Packing entries contiguously reduced pointer/allocation overhead, but insertions/deletions could require shifting/re-encoding bytes and had pathological update-cost concerns.
Modern Redis versions have moved to newer compact encodings such as listpack in relevant places. Therefore ziplist is best treated as historical data-structure context.
The transferable idea is packed representation: save memory/cache misses at the cost of more expensive structural updates.