lihao712 commented on PR #46696: URL: https://github.com/apache/spark/pull/46696#issuecomment-2362575555
> To @lihao712 , Apache Spark (3.0.2+) uses version 1 by default (via [SPARK-33019](https://issues.apache.org/jira/browse/SPARK-33019)) due to the correctness issue of version 1 ([MAPREDUCE-7282](https://issues.apache.org/jira/browse/MAPREDUCE-7282)). > > > As far as I know, after Hadoop 2.7, the algorithm for checking the task commit path is version 2, and the version 1 implementation performs poorly in practice. For tasks with a large number of files, under the algorithm version 2, how can we ensure that there won't be two task commit files for the same partition existing simultaneously in the final directory? > > * [[SPARK-33019][CORE] Use spark.hadoop.mapreduce.fileoutputcommitter.algorithm.version=1 by default #29895](https://github.com/apache/spark/pull/29895) However, the performance of Algorithm 1 is significantly worse than that of Algorithm 2. Have you tested the performance of both algorithms in scenarios where there are a large number of files produced in the partition? Additionally, has Hadoop made any optimizations to improve the performance of Algorithm 1? -- 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]
