update docs

docs/source/user-guide/configs.md

@@ -77,6 +77,7 @@ Environment variables are read during `SessionConfig` initialisation so they mus
 | datafusion.execution.sort_spill_reservation_bytes          | 10485760                  | Specifies the reserved memory for each spillable sort operation to facilitate an in-memory merge. When a sort operation spills to disk, the in-memory data must be sorted and merged before being written to a file. This setting reserves a specific amount of memory for that in-memory sort/merge process. Note: This setting is irrelevant if the sort operation cannot spill (i.e., if there's no `DiskManager` configured).                                                                                                                                                                       |
 | datafusion.execution.sort_in_place_threshold_bytes         | 1048576                   | When sorting, below what size should data be concatenated and sorted in a single RecordBatch rather than sorted in batches and merged.                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
 | datafusion.execution.meta_fetch_concurrency                | 32                        | Number of files to read in parallel when inferring schema and statistics                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
+| datafusion.execution.minimum_parallel_output_files         | 4                         | Guarentees a minimum level of output files running in parallel. RecordBatches will be distributed in round robin fashion to each parallel writer. Each writer is closed and a new file opened once soft_max_rows_per_output_file is reached.                                                                                                                                                                                                                                                                                                                                                            |
 | datafusion.execution.soft_max_rows_per_output_file         | 50000000                  | Target number of rows in output files when writing multiple. This is a soft max, so it can be exceeded slightly. There also will be one file smaller than the limit if the total number of rows written is not roughly divisible by the soft max                                                                                                                                                                                                                                                                                                                                                        |
 | datafusion.execution.max_parallel_ouput_files              | 8                         | This is the maximum number of output files being written in parallel. Higher values can potentially give faster write performance at the cost of higher peak memory consumption.                                                                                                                                                                                                                                                                                                                                                                                                                        |
 | datafusion.execution.max_buffered_batches_per_output_file  | 2                         | This is the maximum number of RecordBatches buffered for each output file being worked. Higher values can potentially give faster write performance at the cost of higher peak memory consumption                                                                                                                                                                                                                                                                                                                                                                                                       |