ibd file very big when convert to innodb engine

I have a special question, the innodb table become very big when I convert table from MyISAM to InnoDB, the table like this:
original table is MyISAM engine, data file and index file size is:


CREATE TABLE `udb_home_follow` (
`uid` int(11) unsigned NOT NULL DEFAULT '0',
`username` varchar(255) NOT NULL DEFAULT '',
`followuid` int(11) unsigned NOT NULL DEFAULT '0',
`fusername` varchar(255) NOT NULL DEFAULT '',
`bkname` varchar(255) NOT NULL DEFAULT '',
`status` tinyint(1) NOT NULL DEFAULT '0',
`mutual` tinyint(1) NOT NULL DEFAULT '0',
`dateline` int(10) unsigned NOT NULL DEFAULT '0',
PRIMARY KEY (`uid`,`followuid`),
KEY `idx_fuid` (`followuid`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8

there is about 60 million records in udb_home_follow table, most of the records seems like this:


+----------+-----------------------+-----------+--------------------+--------+--------+--------+------------+
| uid | username | followuid | fusername | bkname | status | mutual | dateline |
+----------+-----------------------+-----------+--------------------+--------+--------+--------+------------+
| 6235195 | curapikt87 | 14644915 | coolmayi | | 0 | 0 | 1347433303 |
| 17425562 | 1442453108xia | 14919966 | zczczczc0 | | 0 | 0 | 1347433673 |
+----------+-----------------------+-----------+--------------------+--------+--------+--------+------------+

Name: udb_home_follow
Engine: MyISAM
Version: 10
Row_format: Dynamic
Rows: 62833131
Avg_row_length: 31
Data_length: 1948544532
Max_data_length: 281474976710655
Index_length: 1563675648
Data_free: 0

after I execute any of the following sql query, new innodb become very huge :


alter table udb_home_follow engine = innodb;
insert into udb_innodb select * from udb_home_follow;

innodb table, it seems like table Number of lines increased tenfold, and ibd file become to 267G:


Engine: InnoDB
Version: 10
Row_format: Compact
Rows: 641272410
Avg_row_length: 73
Data_length: 237746100224
Max_data_length: 0
Index_length: 33729784832
Data_free: 3306556672

-rw-rw---- 1 mysql mysql 8.7K Aug 18 17:45 udb_innodb.frm
-rw-rw---- 1 mysql mysql 267G Aug 18 20:16 udb_innodb.ibd


my system env :

I have no idea for this error message, thanks a lot for everyone help.

InnoDB stores all records inside a fixed-size unit which is commonly called a “page”. Therefore InnoDB (XtraDB) very inefficiently uses disk space. Try to change row_format to dynamic or compressed (InnoDB compression can increase CPU load in many times).
TokuDB with lzma/lzo compression will be 2-3 times smaller than MyISAM table, and faster InnoDB .
Similar topic: https://www.percona.com/forums/quest…ers-in-7-times