MySQL与PostgreSQL导入数据对比区别

>>>
Running 23.289 Seconds

MySQL 自带mysqlimport：（时间23秒）
[root@mysql56-master ~]# time mysqlimport t_girl '/tmp/t1.csv' --fields-terminated-by=',' --fields-enclosed-by='"' --lines-terminated-by='rn' --use-threads=2 -uroot -proot
t_girl.t1: Records: 1000000 Deleted: 0 Skipped: 0 Warnings: 0

real 0m23.664s
user 0m0.016s
sys 0m0.037s

PostgreSQL 自身COPY：（时间7秒）
t_girl=# copy t1 from '/tmp/t1.csv' with delimiter ',';
COPY 1000000
Time: 7700.332 ms

Psycopg2 驱动copy_to方法：（时间6秒）
[root@postgresql-instance scripts]# python load_data.py
Running 5.969 Seconds.

Pgloader 导入CSV：（时间33秒）
[root@postgresql-instance ytt]# pgloader commands.load
                    table name read imported errors time

                        ytt.t1 1000000 1000000 0 33.514s
------------------------------ --------- --------- --------- --------------
------------------------------ --------- --------- --------- --------------
             Total import time 1000000 1000000 0 33.514s

Pgloader 直接从MySQL 拉数据：（时间51秒）
[root@postgresql-instance ytt]# pgloader commands.mysql
                    table name read imported errors time

               fetch meta data 2 2 0 0.138s
------------------------------ --------- --------- --------- --------------
                            t1 1000000 1000000 0 51.136s
------------------------------ --------- --------- --------- --------------
------------------------------ --------- --------- --------- --------------
------------------------------ --------- --------- --------- --------------
             Total import time 1000000 1000000 0 51.274s

附上commands.load和commands.mysql
commands.load:
LOAD CSV
   FROM '/tmp/ytt.csv' WITH ENCODING UTF-8
        (
           id, rank, log_time
        )
   INTO postgresql://t_girl:t_girl@127.0.0.1:5432/t_girl?ytt.t1
   WITH skip header = 0,
        fields optionally enclosed by '"',
        fields escaped by backslash-quote,
        fields terminated by ','
 
    SET work_mem to '32 MB', maintenance_work_mem to '64 MB';

commands.mysql:
LOAD DATABASE
     FROM mysql://python_user:python_user@192.168.1.131:3306/t_girl?t1
     INTO postgresql://t_girl:t_girl@127.0.0.1:5432/t_girl?ytt.t1
 
 with data only

  SET maintenance_work_mem to '64MB',
      work_mem to '3MB',
      search_path to 'ytt';