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MYSQLD_SAFE(1) | MySQL Database System | MYSQLD_SAFE(1) |
NAME¶
mysqld_safe - MySQL server startup scriptSYNOPSIS¶
mysqld_safe options
DESCRIPTION¶
mysqld_safe is the recommended way to start a mysqld server on Unix. mysqld_safe adds some safety features such as restarting the server when an error occurs and logging runtime information to an error log file. A description of error logging is given later in this section. mysqld_safe tries to start an executable named mysqld. To override the default behavior and specify explicitly the name of the server you want to run, specify a --mysqld or --mysqld-version option to mysqld_safe. You can also use --ledir to indicate the directory where mysqld_safe should look for the server. Many of the options to mysqld_safe are the same as the options to mysqld. See Section 5.1.3, “Server Command Options”. Options unknown to mysqld_safe are passed to mysqld if they are specified on the command line, but ignored if they are specified in the [mysqld_safe] group of an option file. See Section 4.2.6, “Using Option Files”. mysqld_safe reads all options from the [mysqld], [server], and [mysqld_safe] sections in option files. For example, if you specify a [mysqld] section like this, mysqld_safe will find and use the --log-error option:[mysqld] log-error=error.log
•--help
Display a help message and exit.
•--basedir=dir_name
The path to the MySQL installation directory.
•--core-file-size=size
The size of the core file that mysqld should be able to create. The
option value is passed to ulimit -c.
•--datadir=dir_name
The path to the data directory.
•--defaults-extra-file=file_name
The name of an option file to be read in addition to the usual option files.
This must be the first option on the command line if it is used. If the file
does not exist or is otherwise inaccessible, the server will exit with an
error.
•--defaults-file=file_name
The name of an option file to be read instead of the usual option files. This
must be the first option on the command line if it is used.
•--ledir=dir_name
If mysqld_safe cannot find the server, use this option to indicate the
path name to the directory where the server is located.
•--log-error=file_name
Write the error log to the given file. See Section 5.2.2, “The
Error Log”.
•--malloc-lib=[lib_name]
The name of the library to use for memory allocation instead of the system
malloc() library. Any library can be used by specifying its path name, but
there is a shortcut form to enable use of the tcmalloc library that is shipped
with binary MySQL distributions for Linux in MySQL 5.6. It is possible that
the shortcut form will not work under certain configurations, in which case
you should specify a path name instead.
The --malloc-lib option works by modifying the LD_PRELOAD environment
value to affect dynamic linking to enable the loader to find the
memory-allocation library when mysqld runs:
Those lines also suffice for users on any platform who have installed a tcmalloc
package in /usr/lib. To use a specific tcmalloc library, specify its full path
name. Example:
•If the option is not given, or is given without a
value ( --malloc-lib=), LD_PRELOAD is not modified and no attempt is
made to use tcmalloc.
•If the option is given as
--malloc-lib=tcmalloc, mysqld_safe looks for a tcmalloc library
in /usr/lib and then in the MySQL pkglibdir location (for example,
/usr/local/mysql/lib or whatever is appropriate). If tmalloc is found, its
path name is added to the beginning of the LD_PRELOAD value for mysqld.
If tcmalloc is not found, mysqld_safe aborts with an error.
•If the option is given as
--malloc-lib= /path/to/some/library, that full path is
added to the beginning of the LD_PRELOAD value. If the full path points to a
nonexistent or unreadable file, mysqld_safe aborts with an error.
•For cases where mysqld_safe adds a path
name to LD_PRELOAD, it adds the path to the beginning of any existing value
the variable already has.
Linux users can use the libtcmalloc_minimal.so included in binary packages by
adding these lines to the my.cnf file:
[mysqld_safe] malloc-lib=tcmalloc
[mysqld_safe] malloc-lib=/opt/lib/libtcmalloc_minimal.so
•--mysqld=prog_name
The name of the server program (in the ledir directory) that you want to start.
This option is needed if you use the MySQL binary distribution but have the
data directory outside of the binary distribution. If mysqld_safe
cannot find the server, use the --ledir option to indicate the path
name to the directory where the server is located.
•--mysqld-version=suffix
This option is similar to the --mysqld option, but you specify only the
suffix for the server program name. The base name is assumed to be
mysqld. For example, if you use --mysqld-version=debug,
mysqld_safe starts the mysqld-debug program in the ledir
directory. If the argument to --mysqld-version is empty,
mysqld_safe uses mysqld in the ledir directory.
•--nice=priority
Use the nice program to set the server's scheduling priority to the given
value.
•--no-defaults
Do not read any option files. This must be the first option on the command line
if it is used.
•--open-files-limit=count
The number of files that mysqld should be able to open. The option value
is passed to ulimit -n.
Note
You must start mysqld_safe as root for this to function properly.
•--pid-file=file_name
The path name of the process ID file.
•--plugin-dir=dir_name
The path name of the plugin directory.
•--port=port_num
The port number that the server should use when listening for TCP/IP
connections. The port number must be 1024 or higher unless the server is
started by the root system user.
•--skip-kill-mysqld
Do not try to kill stray mysqld processes at startup. This option works
only on Linux.
•--socket=path
The Unix socket file that the server should use when listening for local
connections.
•--syslog, --skip-syslog
--syslog causes error messages to be sent to syslog on systems that
support the logger program. --skip-syslog suppresses the use of syslog;
messages are written to an error log file.
When syslog is used, the daemon.err syslog facility/severity is used for all log
messages.
•--syslog-tag=tag
For logging to syslog, messages from mysqld_safe and mysqld are
written with identifiers of mysqld_safe and mysqld, respectively. To specify a
suffix for the identifiers, use --syslog-tag=tag, which
modifies the identifiers to be mysqld_safe- tag and mysqld-
tag.
•--timezone=timezone
Set the TZ time zone environment variable to the given option value. Consult
your operating system documentation for legal time zone specification
formats.
•--user={user_name|user_id}
Run the mysqld server as the user having the name user_name or the
numeric user ID user_id. (“User” in this context refers
to a system login account, not a MySQL user listed in the grant tables.)
If you execute mysqld_safe with the --defaults-file or
--defaults-extra-file option to name an option file, the option must be
the first one given on the command line or the option file will not be used.
For example, this command will not use the named option file:
mysql> mysqld_safe --port=port_num --defaults-file=file_name
mysql> mysqld_safe --defaults-file=file_name --port=port_num
•The server and databases can be found relative to
the working directory (the directory from which mysqld_safe is
invoked). For binary distributions, mysqld_safe looks under its working
directory for bin and data directories. For source distributions, it looks for
libexec and var directories. This condition should be met if you execute
mysqld_safe from your MySQL installation directory (for example,
/usr/local/mysql for a binary distribution).
•If the server and databases cannot be found
relative to the working directory, mysqld_safe attempts to locate them
by absolute path names. Typical locations are /usr/local/libexec and
/usr/local/var. The actual locations are determined from the values configured
into the distribution at the time it was built. They should be correct if
MySQL is installed in the location specified at configuration time.
Because mysqld_safe tries to find the server and databases relative to
its own working directory, you can install a binary distribution of MySQL
anywhere, as long as you run mysqld_safe from the MySQL installation
directory:
shell> cd mysql_installation_directory shell> bin/mysqld_safe &
•--log-error=file_name: Write
error messages to the named error file.
•--syslog: Write error messages to syslog
on systems that support the logger program.
•--skip-syslog: Do not write error messages
to syslog. Messages are written to the default error log file (
host_name.err in the data directory), or to a named file if the
--log-error option is given.
If none of these options is given, the default is --skip-syslog.
If --log-error and --syslog are both given, a warning is issued
and --log-error takes precedence.
When mysqld_safe writes a message, notices go to the logging destination
(syslog or the error log file) and stdout. Errors go to the logging
destination and stderr.
COPYRIGHT¶
Copyright © 1997, 2016, Oracle and/or its affiliates. All rights reserved. This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/.SEE ALSO¶
For more information, please refer to the MySQL Reference Manual, which may already be installed locally and which is also available online at http://dev.mysql.com/doc/.AUTHOR¶
Oracle Corporation (http://dev.mysql.com/).03/02/2016 | MySQL 5.6 |