cxzl25 opened a new pull request, #8910:
URL: https://github.com/apache/hadoop/pull/8910
### Description of PR
`chooseEvenlyFromRemainingRacks()` (added in HDFS-17052) calls
`Collections.max(nodesPerRack.values())` when an iteration chooses no new node.
If no node could be chosen at all, `results` is empty and this throws
`NoSuchElementException`.
Since it is not a `NotEnoughReplicasException`, it bypasses the fallbacks in
`BlockPlacementPolicyDefault#chooseTarget` (retrying without avoiding stale
nodes, and storage type fallback). For example, an `ALL_SSD` file cannot fall
back to DISK
when there is no SSD, and the write fails.
This PR breaks out of the loop when `results` is still empty. With no node
chosen, the per-rack limit is never what rejects a node, so relaxing
`bestEffortMaxNodesPerRack` cannot help. The original
`NotEnoughReplicasException` is rethrown and the default policy's fallbacks
work again.
### How was this patch tested?
Added
`TestBlockPlacementPolicyRackFaultTolerant#testChooseTargetFallbackStorageType`
### For code changes:
- [ ] Does the title of this PR start with the corresponding JIRA issue id
(e.g. 'HADOOP-17799. Your PR title ...')?
- [ ] Object storage: Have the integration tests been executed and the
endpoint
declared according to the connector-specific documentation? *Note:
Automated CI
testing doesn't cover all cases so manual testing with cloud storage
is still
required.*
- [ ] If adding new dependencies to the code, are these dependencies
licensed in a way that is compatible for inclusion under [ASF
2.0](http://www.apache.org/legal/resolved.html#category-a)?
- [ ] If applicable, have you updated the `LICENSE`, `LICENSE-binary`,
`NOTICE-binary` files?
### AI Tooling
If an AI tool was used:
- [ ] The PR includes the phrase "Contains content generated by <tool>"
where <tool> is the name of the AI tool used.
- [ ] My use of AI contributions follows the ASF legal policy
https://www.apache.org/legal/generative-tooling.html
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
