[doc] Introduce how the read.batch-size option can impact memory cons…

…umption when compaction in write-performance page (apache#1175)

docs/content/maintenance/write-performance.md

@@ -213,4 +213,5 @@ There are three main places in Paimon writer that takes up memory:
 
 * Writer's memory buffer, shared and preempted by all writers of a single task. This memory value can be adjusted by the `write-buffer-size` table property.
 * Memory consumed when merging several sorted runs for compaction. Can be adjusted by the `num-sorted-run.compaction-trigger` option to change the number of sorted runs to be merged.
+* If the row is very large, reading too many lines of data at once can consume a lot of memory when making a compaction. Reducing the `read.batch-size` option can alleviate the impact of this case.
 * The memory consumed by writing columnar (ORC, Parquet, etc.) file, which is not adjustable.