[columnar] [bug] panic query on select count(*) from .. #170
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When can this PR be merged? |
This PR only addresses part of code that could potentially be critical and one to blame based on bug report output and infromation. I was not able to reproduce issue so no test could be created. PR changes execution of parallel worker assignments, so any test that is already in regression and execute parallel execution is one that is testing this PR. |
JerrySievert
approved these changes
Oct 16, 2023
* When stripe assignment for next parallel worker is executing we iterate sequentially to find next stripe that will be used. That could be expensive - especially if number of stripes for table is big. During this loop we are holding shared mutex that will abort if held to long. * Fixed by using second column from index to faster assign stripe for worker.
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rebased, can merge if build passes. |
This was referenced Oct 17, 2023
Merged
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When stripe assignment for next parallel worker is executing we iterate sequentially to find next stripe that will be used. That could be expensive - especially if number of stripes for table is big. During this loop we are holding shared mutex that will abort if held to long.
Fixed by using second column from index to faster assign stripe for worker.