The shards_table (DashMap<IggyNamespace, PartitionLocation>) is the shared lookup table that maps partition namespaces to their owning shard. It is queried on every message routing decision (find_shard, resolve) but only written to during partition creation, deletion, or rebalancing, which is ready-heavy workload.
papaya is a lock-free concurrent hash map specifically optimized for read-heavy access patterns. Switching shards_table from DashMap to papaya should reduce contention on the hot routing path.
The shards_table (
DashMap<IggyNamespace, PartitionLocation>) is the shared lookup table that maps partition namespaces to their owning shard. It is queried on every message routing decision (find_shard, resolve) but only written to during partition creation, deletion, or rebalancing, which is ready-heavy workload.papayais a lock-free concurrent hash map specifically optimized for read-heavy access patterns. Switchingshards_tablefrom DashMap to papaya should reduce contention on the hot routing path.