# DataframeWriter tuning options

Partitioning management is a critical factor in optimized performance because too few partitions may result in underused resources and too many partitions may result in too many resources for managing small tasks. Partitioning your data more evenly helps avoid these problems. Because partitioning is pushed down to the data in the output files during the `DataFrameWriter .save()` call, repartitioning occurs when writing files.

| Option                        | Description                                                                                                                                                                                                                                         | Value type              | Example value    |
| ----------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------- | ---------------- |
| **write.partitionBy.columns** | Partitions the output by the given columns on the file system. See the [Spark API documentation](https://spark.apache.org/docs/2.3.0/api/java/org/apache/spark/sql/DataFrameWriter.html#partitionBy-java.lang.String...-) for more information.     | Comma separated strings | column1, column2 |
| **write.bucketBy.columns**    | Buckets the output by the given columns. See the [Spark API documentation](https://spark.apache.org/docs/2.3.0/api/java/org/apache/spark/sql/DataFrameWriter.html#bucketBy-int-java.lang.String-scala.collection.Seq-) for more information.        | Comma separated strings | column1, column2 |
| **write.sortBy.columns**      | Sorts the output in each bucket by the given columns. See the [Spark API documentation](https://spark.apache.org/docs/2.3.0/api/java/org/apache/spark/sql/DataFrameWriter.html#sortBy-java.lang.String-scala.collection.Seq-) for more information. | Comma separated strings | column1, column2 |
| **write.bucketBy.numBuckets** | Buckets the output by the given columns. See the [Spark API documentation](https://spark.apache.org/docs/2.3.0/api/java/org/apache/spark/sql/DataFrameWriter.html#bucketBy-int-java.lang.String-scala.collection.Seq-) for more information.        | Integer                 | 5                |


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