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MySQL NDB Cluster 7.2  /  NDB Cluster Programs  / — NDBCLUSTER Size Requirement Estimator

6.25 — 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.

The following table includes options that are specific to the NDB Cluster program Additional descriptions follow the table. For options common to most NDB Cluster programs (including, see Section 6.27, “Options Common to NDB Cluster Programs — Options Common to NDB Cluster Programs”.

Table 6.21 Command-line options for the program

Format Description Added, Deprecated, or Removed


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

All MySQL 5.5 based releases


Specify host and optional port as host[:port]

All MySQL 5.5 based releases


Specify a socket to connect to

All MySQL 5.5 based releases


Specify a MySQL user name

All MySQL 5.5 based releases


Specify a MySQL user password

All MySQL 5.5 based releases


Set output format (text or HTML)

All MySQL 5.5 based releases


Skip any tables in a comma-separated list of tables

All MySQL 5.5 based releases


Skip any databases in a comma-separated list of databases

All MySQL 5.5 based releases


Saves all queries to the database into the file specified

All MySQL 5.5 based releases


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

All MySQL 5.5 based releases


Designates a table to handle unique index size calculations

All MySQL 5.5 based releases


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. In NDB 7.2.6 and later, 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:

shell> --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:

shell> --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: