zhiliang-wu opened a new pull request, #11131:
URL: https://github.com/apache/seatunnel/pull/11131
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### Purpose of this pull request
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request adds checkstyle plugin.-->
Currently, the MaxcomputeSource divides the total record count into massive
contiguous blocks sequentially (e.g., Reader 0 gets the first 25% of the table,
Reader 1 gets the next 25%). Furthermore, it stores these splits internally
using a HashSet, which completely scrambles the split assignment order before
they are processed by the readers.
Because of this, if a user uses ORDER BY or RANGE CLUSTERED BY in their
MaxCompute table to prioritize data, running SeaTunnel with parallelism > 1
destroys this ordering entirely.
This PR introduces a Round-Robin Split Assignment logic:
Replaces the massive contiguous block chunking with striped/round-robin
chunking (e.g. Reader 0 gets chunk 1, Reader 1 gets chunk 2). This allows all
parallel readers to pull from the "top" of the table simultaneously, preserving
a high-level priority order across multiple threads.
Replaces HashSet with LinkedHashSet in MaxcomputeSourceSplitEnumerator to
guarantee that the chronological insertion order of splits is strictly
preserved when assigning them to the readers.
### Does this PR introduce _any_ user-facing change?
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No. This PR only modifies the internal split enumeration and distribution
logic for the MaxCompute Source. It introduces no new configuration options and
does not break any existing contracts. It purely optimizes the reading order to
be more evenly distributed across parallel readers.
### How was this patch tested?
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Ran mvn clean install -pl seatunnel-connectors-v2/connector-maxcompute -am
-DskipTests to verify compilation and dependency integrity.
Manually tested the execution graph locally to verify that splits are
correctly striped and assigned in round-robin order without hash scrambling.
### Check list
* [ ] If any new Jar binary package adding in your PR, please add License
Notice according
[New License
Guide](https://github.com/apache/seatunnel/blob/dev/docs/en/developer/new-license.md)
* [ ] If necessary, please update the documentation to describe the new
feature. https://github.com/apache/seatunnel/tree/dev/docs
* [ ] If necessary, please update `incompatible-changes.md` to describe the
incompatibility caused by this PR.
* [ ] If you are contributing the connector code, please check that the
following files are updated:
1. Update
[plugin-mapping.properties](https://github.com/apache/seatunnel/blob/dev/plugin-mapping.properties)
and add new connector information in it
2. Update the pom file of
[seatunnel-dist](https://github.com/apache/seatunnel/blob/dev/seatunnel-dist/pom.xml)
3. Add ci label in
[label-scope-conf](https://github.com/apache/seatunnel/blob/dev/.github/workflows/labeler/label-scope-conf.yml)
4. Add e2e testcase in
[seatunnel-e2e](https://github.com/apache/seatunnel/tree/dev/seatunnel-e2e/seatunnel-connector-v2-e2e/)
5. Update connector
[plugin_config](https://github.com/apache/seatunnel/blob/dev/config/plugin_config)
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