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Analysing Parallel Execution Skew - Video Tutorial

Along the new mini series "Parallel Execution Skew" at "" that provides some information what you can do if you happen to have a parallel SQL execution that is affected by work distribution problems I'm publishing a series of video tutorials that explain how you can actually detect and measure whether a SQL execution is affected by skew or not.

Originally this tutorial was planned as one part (Part 5 actually) of the XPLAN_ASH video tutorial series, however so far I've only managed to publish just the inital two parts of that series, and these are already a bit outdated as I've released new versions of the XPLAN_ASH tool with significant changes and enhancements since then.

Since this tutorial covers a lot of information and I don't want to bother you watching a single multi-hour video, I'm splitting this tutorial into four parts:

  • Brief introduction
  • Explaining Data Flow Operations (DFOs)
  • Analysing Parallel Execution Skew without Diagnostic / Tunink Pack license
  • Analysing Parallel Execution Skew with Diagnostic / Tunink Pack license

So here is the initial part, a brief introduction what the "Parallel Execution Skew" problem is about:

The links mentioned at the beginning of the video are:
Webinar recording "Analysing and Troubleshooting Parallel Execution"
OTN mini series "Understanding Parallel Execution"