in flink-connector-opensearch/src/main/java/org/apache/flink/streaming/connectors/opensearch/OpensearchSink.java [498:505]
private void configureFlushInterval(BulkProcessor.Builder bulkProcessorBuilder) {
if (bulkProcessorFlushIntervalMillis == -1) {
bulkProcessorBuilder.setFlushInterval(null);
} else {
bulkProcessorBuilder.setFlushInterval(
TimeValue.timeValueMillis(bulkProcessorFlushIntervalMillis));
}
}