Diagnose uneven parallelism by comparing CXPACKET and CXCONSUMER with per-thread row counts in plans and live query profiles.
Exchange Spill: When Parallel Streams Write to tempdb
Tempdb writes during a parallel query, with no sort warning in sight? Here is a demo that spills every time, and how to find the operator.
Loading Partitions in Parallel
Loading partitions in parallel uses separate staging tables, controlled workers, and partition switching to publish data without chaotic locks.
Computed Column UDFs: Why Every Query on the Table Goes Serial
A computed column that calls a scalar function can block parallel plans for queries that never read it. Here is how to spot it and test a fix.
Intra-Query Parallel Deadlock: When One Query Blocks Itself
No error, no deadlock graph, just a report that is slow on some runs. Here is a demo where one query deadlocks with itself, and how to fix it.
Setting MAXDOP and Cost Threshold Sensibly
MAXDOP and cost threshold work together to shape parallel plans; inspect current values, test a change, and watch real workload effects.