diff --git a/core/src/main/java/org/apache/spark/shuffle/unsafe/UnsafeShuffleExternalSorter.java b/core/src/main/java/org/apache/spark/shuffle/unsafe/UnsafeShuffleExternalSorter.java index 3d1ef0c48adc5..e73ba39468828 100644 --- a/core/src/main/java/org/apache/spark/shuffle/unsafe/UnsafeShuffleExternalSorter.java +++ b/core/src/main/java/org/apache/spark/shuffle/unsafe/UnsafeShuffleExternalSorter.java @@ -122,6 +122,10 @@ public UnsafeShuffleExternalSorter( this.maxRecordSizeBytes = pageSizeBytes - 4; this.writeMetrics = writeMetrics; initializeForWriting(); + + // preserve first page to ensure that we have at least one page to work with. Otherwise, + // other operators in the same task may starve this sorter (SPARK-9709). + acquireNewPageIfNecessary(pageSizeBytes); } /**