The sum of the execution time less than actual time from performance_schema

[WaterBin Lin]

when I LOAD DATA into TokuDB, I found as the following:

mysql> 

mysql> SELECT EVENT_ID, TRUNCATE(TIMER_WAIT/1000000000000,6) as Duration, SQL_TEXT 

    ->   FROM performance_schema.events_statements_history_long WHERE SQL_TEXT like '%load%';

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

| EVENT_ID | Duration  | SQL_TEXT                                                                                                                                       |

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

|       36 | 26.780653 | LOAD DATA LOCAL INFILE '/data1/dbbak/tokuLoadTest/file/65535_20150911_1500.log_157' INTO TABLE db_load.tb_tokudb_zlib FIELDS TERMINATED BY '|' |

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

1 row in set (0.00 sec)

mysql> SELECT event_name AS Stage, TRUNCATE(TIMER_WAIT/1000000000000,6) AS Duration 

    ->   FROM performance_schema.events_stages_history_long WHERE NESTING_EVENT_ID=36;

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

| Stage                                  | Duration |

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

| stage/sql/init                         | 0.000049 |

| stage/sql/checking permissions         | 0.000006 |

| stage/sql/Opening tables               | 0.000032 |

| stage/sql/System lock                  | 0.073764 |

| stage/sql/Waiting for query cache lock | 0.000002 |

| stage/sql/query end                    | 0.000081 |

| stage/sql/closing tables               | 0.000049 |

| stage/sql/freeing items                | 0.000018 |

| stage/sql/logging slow query           | 0.000034 |

| stage/sql/cleaning up                  | 0.000002 |

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

10 rows in set (0.00 sec)

mysql>  

[WaterBin Lin]

TokuDB Spend a lot of time where  to go ?

在 2015年9月22日星期二 UTC+8下午6:03:46，WaterBin Lin写道：