Hi Harish, you don't mention what level of Db2 you are running for the test, and if you are using Row Store or Columnar in your test in which you observe 2x the sortheap being used.Thanks.Ian
Db2 Runtime and Optimizer Development
The scenario is observed in 10.5 Fp8 and 11.1 and 11.5 also with ROW organized tables.
It is working properly in 9.7 Fp4
I have even created videos demonstrating the scenario.
https://youtu.be/CfiF5IEbwwU Using Shared Sort Memory
https://youtu.be/TSEqdLT4ZFg using Private Sort Memory
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