The no_wait method instructs the DSI to initiate the next transaction without waiting for the previous transaction to commit.
no_wait assumes that your primary applications are designed to avoid conflicting updates, or that dsi_partitioning_rule is used effectively to reduce or eliminate contention. Adaptive Server does not hold update locks unless dsi_isolation_level has been set to 3. The method assumes little contention between parallel transactions and results in the nearly parallel execution shown in the "Thread Timing with wait_for_commit Serialization Method" diagram.
no_wait provides the better opportunity for increased performance, but also provides the greater risk of creating contentions.