How to troubleshoot when a customer complains the data steward application is very slow - including taking more than 10 seconds to open a BOV, taking more than 1 minute to check out records in a duplicate management workflow, etc.
Slow BOVs/Navigating through the data
Step 1: Collect information
- Turn on logging for the data steward application. Follow these instructions.
- Gather benchmarks metrics to track what is slow. Time however long it takes to perform the task that the customer complains is sluggish.
- For example, pick a BOV. Open the golden view only. See error log for how long that task took and retrieve the SQL that ran.
- Run the SQL in SQL Developer. Does it take the same amount of time to execute as it does in Semarchy?
- Get the an explain plan.
# 1 Culprit for slow performance: Sorting
Sort is a highly suspicious component that might be causing bad performance. Sorting requires ordering and the order by is a very expensive task that can cause the application to slow down significantly.
Look at the "Sort order by stopkey" cost. Does it seem like a higher cost than the other tasks (like joins) in the explain plan?
To test, comment out the order by statement. Execution now takes less than 10 seconds? Probably an issue with sorting.
Step 2: Troubleshooting in Semarchy
- Under Preferences → Data Stewardship, uncheck Predictable Pagination.
- Open the BOV. Under More, look at Customized Sort. Are there any attributes sorted? If yes, remove all attributes. This should increase speed of application. The more attributes sorted, the longer the BOV will take because Oracle is taking a very long time to sort the attributes when the BOV opens.
- No attributes under customized sort? What about Customized Sort defined in the Workbench under the BOV configuration? If Customized Sort is turned on and there's a sort expression, turn off Customized Sort and performance should be improved.
- If there's still bad performance or NPE when opening BOVs, sort preferences might have a problem. Go to Preferences, Under Filters restore defaults. Under Sort Criteria, also restore to defaults. Getting rid of Sort and sort preferences usually solves the problem. What can happen is a user who is waiting a long time for a BOV to open can get impatient and click the refresh button on the browser. This causes the preferences to get in a weird place and resetting them should fix any exceptions.
Dupes Mgmt Workflow takes a long time
Step 1: Troubleshooting in Semarchy
Check there is no Customized Sort
Under display settings, uncheck Autofit columns, Colorize consolidated Master values, Colors Golden IDs.
Best practice: Should not check out more than 1K records in basket for dupes mgmt. Tweak match rules to do autoconfirm if a data steward is checking out more than 1K records to blindly confirm them.
Good idea to remove records from basket. Don’t just cancel out of workflows. Actually Select All and hit Delete. If you only cancel out of workflows and do not actually delete the records, you end up having huge amounts of data in UG and UM tables. Probably hurts performance. Can write a script to prune the UG and UM tables.
DE workflow takes a long time to finish processing integration job
Probably have Calculate statistics turned on. Check out this article for details.