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MySQL 5.7 Reference Manual  /  ...  / — NDBCLUSTER Size Requirement Estimator

21.5.28 — NDBCLUSTER Size Requirement Estimator

This is a Perl script that can be used to estimate the amount of space that would be required by a MySQL database if it were converted to use the NDBCLUSTER storage engine. Unlike the other utilities discussed in this section, it does not require access to an NDB Cluster (in fact, there is no reason for it to do so). However, it does need to access the MySQL server on which the database to be tested resides.


  • A running MySQL server. The server instance does not have to provide support for NDB Cluster.

  • A working installation of Perl.

  • The DBI module, which can be obtained from CPAN if it is not already part of your Perl installation. (Many Linux and other operating system distributions provide their own packages for this library.)

  • A MySQL user account having the necessary privileges. If you do not wish to use an existing account, then creating one using GRANT USAGE ON db_name.*—where db_name is the name of the database to be examined—is sufficient for this purpose. can also be found in the MySQL sources in storage/ndb/tools.

Options that can be used with are shown in the following table. Additional descriptions follow the table.

Table 21.44 Command-line options used with the program

Format Description Added, Deprecated, or Removed


Database or databases to examine; a comma-delimited list; default is ALL (use all databases found on server)

(Supported in all NDB releases based on MySQL 5.7)


Specify host and optional port in host[:port] format

(Supported in all NDB releases based on MySQL 5.7)


Specify socket to connect to

(Supported in all NDB releases based on MySQL 5.7)


Specify MySQL user name

(Supported in all NDB releases based on MySQL 5.7)


Specify MySQL user password

(Supported in all NDB releases based on MySQL 5.7)


Set output format (text or HTML)

(Supported in all NDB releases based on MySQL 5.7)


Skip any tables in comma-separated list

(Supported in all NDB releases based on MySQL 5.7)


Skip any databases in comma-separated list

(Supported in all NDB releases based on MySQL 5.7)


Saves all queries on database into file specified

(Supported in all NDB releases based on MySQL 5.7)


Loads all queries from file specified; does not connect to database

(Supported in all NDB releases based on MySQL 5.7)


Designates table to handle unique index size calculations

(Supported in all NDB releases based on MySQL 5.7)


perl [--database={db_name|ALL}] [--hostname=host[:port]] [--socket=socket] \
      [--user=user] [--password=password]  \
      [--help|-h] [--format={html|text}] \
      [--loadqueries=file_name] [--savequeries=file_name]

By default, this utility attempts to analyze all databases on the server. You can specify a single database using the --database option; the default behavior can be made explicit by using ALL for the name of the database. You can also exclude one or more databases by using the --excludedbs option with a comma-separated list of the names of the databases to be skipped. Similarly, you can cause specific tables to be skipped by listing their names, separated by commas, following the optional --excludetables option. A host name can be specified using --hostname; the default is localhost. You can specify a port in addition to the host using host:port format for the value of --hostname. The default port number is 3306. If necessary, you can also specify a socket; the default is /var/lib/mysql.sock. A MySQL user name and password can be specified the corresponding options shown. It also possible to control the format of the output using the --format option; this can take either of the values html or text, with text being the default. An example of the text output is shown here:

$> --database=test --socket=/tmp/mysql.sock report for database: 'test' (1 tables)
Connected to: DBI:mysql:host=localhost;mysql_socket=/tmp/mysql.sock

Including information for versions: 4.1, 5.0, 5.1


DataMemory for Columns (* means varsized DataMemory):
         Column Name            Type  Varsized   Key  4.1  5.0   5.1
     HIDDEN_NDB_PKEY          bigint             PRI    8    8     8
                  c2     varchar(50)         Y         52   52    4*
                  c1         int(11)                    4    4     4
                                                       --   --    --
Fixed Size Columns DM/Row                              64   64    12
   Varsize Columns DM/Row                               0    0     4

DataMemory for Indexes:
   Index Name                 Type        4.1        5.0        5.1
      PRIMARY                BTREE         16         16         16
                                           --         --         --
       Total Index DM/Row                  16         16         16

IndexMemory for Indexes:
               Index Name        4.1        5.0        5.1
                  PRIMARY         33         16         16
                                  --         --         --
           Indexes IM/Row         33         16         16

Summary (for THIS table):
                                 4.1        5.0        5.1
    Fixed Overhead DM/Row         12         12         16
           NULL Bytes/Row          4          4          4
           DataMemory/Row         96         96         48
                    (Includes overhead, bitmap and indexes)

  Varsize Overhead DM/Row          0          0          8
   Varsize NULL Bytes/Row          0          0          4
       Avg Varside DM/Row          0          0         16

                 No. Rows          0          0          0

        Rows/32kb DM Page        340        340        680
Fixedsize DataMemory (KB)          0          0          0

Rows/32kb Varsize DM Page          0          0       2040
  Varsize DataMemory (KB)          0          0          0

         Rows/8kb IM Page        248        512        512
         IndexMemory (KB)          0          0          0

Parameter Minimum Requirements
* indicates greater than default

                Parameter     Default        4.1         5.0         5.1
          DataMemory (KB)       81920          0           0           0
       NoOfOrderedIndexes         128          1           1           1
               NoOfTables         128          1           1           1
         IndexMemory (KB)       18432          0           0           0
    NoOfUniqueHashIndexes          64          0           0           0
           NoOfAttributes        1000          3           3           3
             NoOfTriggers         768          5           5           5

For debugging purposes, the Perl arrays containing the queries run by this script can be read from the file specified using can be saved to a file using --savequeries; a file containing such arrays to be read during script execution can be specified using --loadqueries. Neither of these options has a default value.

To produce output in HTML format, use the --format option and redirect the output to a file, as shown here:

$> --database=test --socket=/tmp/mysql.sock --format=html > ndb_size.html

(Without the redirection, the output is sent to stdout.)

The output from this script includes the following information: