MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6

4.6.8 mysqldumpslow — Summarize Slow Query Log Files

The MySQL slow query log contains information about queries that take a long time to execute (see Section 5.4.5, “The Slow Query Log”). mysqldumpslow parses MySQL slow query log files and summarizes their contents.

Normally, mysqldumpslow groups queries that are similar except for the particular values of number and string data values. It abstracts these values to N and 'S' when displaying summary output. To modify value abstracting behavior, use the -a and -n options.

Invoke mysqldumpslow like this:

shell> mysqldumpslow [options] [log_file ...]

Example of usage:

shell> mysqldumpslow

Reading mysql slow query log from /usr/local/mysql/data/mysqld57-slow.log
Count: 1  Time=4.32s (4s)  Lock=0.00s (0s)  Rows=0.0 (0), root[root]@localhost
 insert into t2 select * from t1

Count: 3  Time=2.53s (7s)  Lock=0.00s (0s)  Rows=0.0 (0), root[root]@localhost
 insert into t2 select * from t1 limit N

Count: 3  Time=2.13s (6s)  Lock=0.00s (0s)  Rows=0.0 (0), root[root]@localhost
 insert into t1 select * from t1

mysqldumpslow supports the following options.

Table 4.21 mysqldumpslow Options

Format Description
-a Do not abstract all numbers to N and strings to 'S'
-n Abstract numbers with at least the specified digits
--debug Write debugging information
-g Only consider statements that match the pattern
--help Display help message and exit
-h Host name of the server in the log file name
-i Name of the server instance
-l Do not subtract lock time from total time
-r Reverse the sort order
-s How to sort output
-t Display only first num queries
--verbose Verbose mode