我用sysbench造了1亿条数据，mysql用了30分钟，tidb总共花了3个小时，感觉tidb在批量插入时比较慢，如果后面程序做分页查询会很慢的.

count总数、降序排序也比mysql慢。

tidb 执行时间，count 一亿条数据用了1分22秒多， order by id 升序几毫秒，但desc降序花了9秒多，limit 1000反而比limit 1要快很多:

mysql> select id from sbtest1 order by id desc limit 10;

+-----------+

| id |

+-----------+

| 100000000 |

| 99999999 |

| 99999998 |

| 99999997 |

| 99999996 |

| 99999995 |

| 99999994 |

| 99999993 |

| 99999992 |

| 99999991 |

+-----------+

10 rows in set (9.90 sec)

mysql> select count(id) from sbtest1;

+-----------+

| count(id) |

+-----------+

| 100000000 |

+-----------+

1 row in set (1 min 22.55 sec)

mysql> status;

mysql Ver 14.14 Distrib 5.7.20, for Linux (x86_64) using EditLine wrapper

Connection id: 25

Current database: sysbench

Current user: root@192.168.4.76

SSL: Not in use

Current pager: stdout

Using outfile: ''

Using delimiter: ;

Server version: 5.7.1-TiDB-v1.1.0-alpha-195-g8a5b8d5 MySQL Community Server (Apache License 2.0)

Protocol version: 10

Connection: 192.168.4.76 via TCP/IP

Server characterset: latin1

Db characterset: utf8

Client characterset: utf8

Conn. characterset: utf8

TCP port: 4000

mysql 执行时间，count 一亿条数据用了34秒多， order by id 降序只花了几十毫秒:

mysql> select id from sbtest1 order by id desc limit 10;

+-----------+

| id |

+-----------+

| 100000000 |

| 99999999 |

| 99999998 |

| 99999997 |

| 99999996 |

| 99999995 |

| 99999994 |

| 99999993 |

| 99999992 |

| 99999991 |

+-----------+

10 rows in set (0.01 sec)

mysql> select count(id) from sbtest1;

+-----------+

| count(id) |

+-----------+

| 100000000 |

+-----------+

1 row in set (34.55 sec)

mysql> status;

mysql Ver 14.14 Distrib 5.7.20, for Linux (x86_64) using EditLine wrapper

Connection id: 284

Current database: sysbench

Current user: root@192.168.4.76

SSL: Cipher in use is DHE-RSA-AES256-SHA

Current pager: stdout

Using outfile: ''

Using delimiter: ;

Server version: 5.7.20 MySQL Community Server (GPL)

Protocol version: 10

Connection: 192.168.100.19 via TCP/IP

Server characterset: latin1

Db characterset: latin1

Client characterset: utf8

Conn. characterset: utf8

TCP port: 3306

Uptime: 4 days 6 hours 9 min 57 sec

Threads: 3 Questions: 274077 Slow queries: 0 Opens: 3504 Flush tables: 1 Open tables: 299 Queries per second avg: 0.745