kudu每秒钟只能写入1000条数据

目前有6台机器，每台机器配置40核 160G内存 9T固态硬盘，然后使用CDH6.3.1部署了kudu1.10.0集群，其中一台为master，6台也同时作为Tablet Server。
然后做了如下优化：
memory_limit_hard_bytes 40G
block_cache_capacity_mb 10G
maintenance_manager_num_threads 8
然后创建了一张test表，四个字段（bigint,decimal,string,string），哈希分区成4个分区。
然后程序如下，往这张表插入1000条数据耗时1秒（有时候需要2-3秒），这也太慢了？各位看看如何优化，或者问题出在哪里？不甚感激！
public class KuduUtils {
public static KuduClient getKuduClient() {
return new KuduClient.KuduClientBuilder(AppParams.kudu_url()).defaultSocketReadTimeoutMs(600000).build();
}

public static void main(String[] args) throws Exception {
    KuduClient kuduClient = new KuduClient.KuduClientBuilder("bigdata-0:7051").build();
    int bufferSpace = 10000;
    KuduTable kuduTable = kuduClient.openTable("impala::test.test");
    KuduSession kuduSession = kuduClient.newSession();
    kuduSession.setFlushMode(SessionConfiguration.FlushMode.MANUAL_FLUSH);
    kuduSession.setMutationBufferSpace(bufferSpace);

    long l = System.currentTimeMillis();
    long count = 0;
    //准备数据
    for (int i = 1; i <= 1000; i++) {
        Upsert insert = kuduTable.newUpsert();
        PartialRow insertRow = insert.getRow();
        //设置字段的内容
        insertRow.addLong("id", i);
        insertRow.addDecimal("ff", BigDecimal.valueOf(i));
        insertRow.addString("aa", "gfsdfdseeedddddddgfdgfsdfdseeedddddddgfdgfsdfdseeedddddddgfdgfsdfdsee");
        insertRow.addString("cc", "gfsdfdseeedddddddgfdgfsdfdseeedddddddgfdgfsdfdseeedddddddgfdgfsdfdsee");
        kuduSession.apply(insert);
        count++;
        if (count > bufferSpace / 2) {
            count = 0;
            kuduSession.flush();
        }
    }

    kuduSession.close();
    kuduClient.close();
    System.out.println(System.currentTimeMillis() - l);
}

}

create table test.test(id bigint,ff decimal(38,18),aa string,cc string,primary key(id)) partition by hash partitions 4 stored as kudu

JAVA代码没问题，我这挺快的，你的schema建表语句贴下呗

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