Repository navigation
Add skewness metric to nodes that execute in partitioned mode (#25977) - #188
Merged
Merged
Conversation
…#25977) <!-- We generally require a GitHub issue to be filed for all bug fixes and enhancements and this helps us generate change logs for our releases. You can link an issue to this PR using the GitHub syntax. For example `Closes #123` indicates that this PR will close issue #123. --> Related to apache#23237 and [feat(metric): Add output skewness metric to detect skewed plans easier](apache#21211) - Closes #. I think it would be useful to add the skewness metric for nodes that execute in partitioned mdoe -- right now the only node that includes that metric in the explain analyze is DataSourceExec for parquet. This is specially useful to check how many partitions were idle during Aggregations or HashJoins for example. The PR adds a new metric `output_rows_skew` in the Explain Analyze output for the following nodes: - RepartitionExec - HashJoinExec - AggregateExec - BoundedWindowAggExec - WindowAggExec Note that for a plan that has a Parquet DataSource the skewness might not be the same as for the rest of the nodes, for example we might have the following scenario: ``` DataSourceExec [100, 100, 100, 100] → 0% skewness, data is even FilterExec [100, 0, 0, 0] → 100% (filter only matches in partition 0) AggregateExec [ 3, 0, 0, 0] → 100% (Partial: groups, not rows) RepartitionExec Hash [1, 1, 1, 0] → ~11% (3 groups re-spread by key) ``` I added a Explain Analyze test Yes, a new metric will show in the explain analyze plan for the nodes mentioned above. (cherry picked from commit c2baac5)
gabotechs
approved these changes
Oct 6, 2026
Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## branch-55 #188 +/- ##
==========================================
Coverage 81.19% 81.19%
==========================================
Files 1111 1111
Lines 387468 387474 +6
Branches 387468 387474 +6
==========================================
+ Hits 314590 314608 +18
+ Misses 54370 54364 -6
+ Partials 18508 18502 -6 ☔ View full report in Codecov by Harness. 🚀 New features to boost your workflow:
|
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Cherry picks apache#25977