What is SQL Server CXPACKET vs CXCONSUMER wait internal difference?

CXPACKET represents parallel worker synchronization, while CXCONSUMER represents benign consumer-side waits.

In parallel query execution, SQL Server splits work into threads. CXPACKET occurs when threads wait for others in a parallel exchange operator. Historically it was considered a bottleneck, but modern SQL Server versions introduced CXCONSUMER to separate harmless waiting from actual imbalance. CXCONSUMER represents consumer threads waiting for producers and is typically not a performance issue. Real problems arise when producer threads are skewed due to uneven data distribution or bad parallel plans.