Page History

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Other aggregations are possible based on the different dimensions in the ASH data.

Tuning Example

Here is an example screen shot of the same batch job being run four times. Between each run performance modifications are made based on what was seen in the in the profiling load chart:

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With the load chart we can quickly and easily identify the bottlenecks in the database, take corrective actions, and see the results. In the first run, almost all the time is spent waiting, in the second run we eliminated a bottleneck but we actually spent more time - the bottleneck was worse. Sometime this happens as eliminating one bottleneck causes great contention on the next bottleneck. (You can see the width of the run, the time it ran, is wider in run 2). By the third run, we are using more CPU and the run time is faster and finally by the 4th run all the time spent is on CPU, no waiting, and the run is the fastest by far.