nsivabalan opened a new pull request, #12938: URL: https://github.com/apache/hudi/pull/12938
### Change Logs Bloom index data skew bucket index partitioner. Fixing bloom index to tackle data skews in write path. For bucketized bloom, fixing the way we deduce the buckets per file group. Fixing the parallelism value for sort partitioner w/ bloom index. [Within each filegroup, we were determining the parallelism](https://github.com/apache/hudi/blob/aeebfcfcec271e8ff8f37e7f7ef2418d386f4c76/hudi-client/hudi-spark-client/src/main/java/org/apache/hudi/index/bloom/BucketizedBloomCheckPartitioner.java#L86) as Math.min(targetParallelism, totalBuckets). In this case, if incoming dataframe has 1 just spark partition, even though we could have computed the required buckets to be 10 (for eg), we might confine to just 1 bucket due to Math.min(). hence, resulting in 1 spark partition dealing with too many keys to be compared against. So, fixing this with this patch. Fix: If the bloom index parallelism is dynamically derived, we can go with Math.max instead of Math.min. This will ensure, we honor the total computed buckets instead of relying on dynamically derived parallelism from higher layer. But if the bloom index parallelism is explicitly overridden by the user, we can leave it as Math.min. ### Impact No data skews with bucketized partitioner with bloom index. ### Risk level (write none, low medium or high below) low ### Documentation Update _Describe any necessary documentation update if there is any new feature, config, or user-facing change. If not, put "none"._ - _The config description must be updated if new configs are added or the default value of the configs are changed_ - _Any new feature or user-facing change requires updating the Hudi website. Please create a Jira ticket, attach the ticket number here and follow the [instruction](https://hudi.apache.org/contribute/developer-setup#website) to make changes to the website._ ### Contributor's checklist - [ ] Read through [contributor's guide](https://hudi.apache.org/contribute/how-to-contribute) - [ ] Change Logs and Impact were stated clearly - [ ] Adequate tests were added if applicable - [ ] CI passed -- 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]
