Skewed Query Processing Across Nodes
Parallel node efficiency is a matter of how evenly the workload is shared among nodes. The more evenly the nodes share the work, the higher the efficiency.
You can calculate parallel node efficiency by dividing average node utilization by maximum node utilization, and identify skewed processing across nodes.
|
IF parallel node |
THEN … |
|
is nearly 100% |
the better the nodes are working together. |
|
falls significantly below 100% |
in that time period, one or a few nodes are working harder than the others. |
|
falls below 60% more often than a couple of sampling periods |
your installation is not taking advantage of the parallel architecture. |
Possible causes of skewed node processing include: