public boolean isFullNecessary() {
    if (!reachFullInterval()) {
      return false;
    }
    return anyDeleteExist() || fragmentFileCount >= 2 || undersizedSegmentFileCount >= 2 ||
        rewriteSegmentFileCount > 0 || rewritePosSegmentFileCount > 0;
  }
Segment files has enough content.

<p>1. The total size of all undersized segment files is greater than target size

<p>2. There are two undersized segment file that can be merged into one
iceberg/iceberg-handler/src/main/java/org/apache/iceberg/mr/hive/compaction/evaluator/amoro/CommonPartitionEvaluator.java