content_image/822126.jpg
Write the error log to the given file. See Section 5.4.2, “The Error Log” . 

• --mysqld-safe-log-timestamps 

This option controls the format for timestamps in log output produced by mysqld_safe . The following list describes the permitted values. For any other value, mysqld_safe  logs a warning and uses UTC format. 

• UTC , utc 

ISO 8601 UTC format (same as --log_timestamps=UTC  for the server). This is the default. 

• SYSTEM , system 

ISO 8601 local time format (same as --log_timestamps=SYSTEM  for the server). 

• HYPHEN , hyphen 

YY-MM-DD h:mm:ss  format, as in mysqld_safe  for MySQL 5.6. 

• LEGACY , legacy 

YYMMDD hh:mm:ss  format, as in mysqld_safe  prior to MySQL 5.6. 

• --malloc-lib=[ lib_name ] 

The name of the library to use for memory allocation instead of the system malloc()  library. The option value must be one of the directories /usr/lib , /usr/lib64 , /usr/lib/i386-linux-gnu , or / usr/lib/x86_64-linux-gnu . 

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: 

•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 . 

•Prior to MySQL 8.0.21, if the option is given as --malloc-lib=tcmalloc , mysqld_safe  looks for a tcmalloc  library in /usr/lib . 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. 

As of MySQL 8.0.21, tcmalloc  is not a permitted value for the --malloc-lib  option. 

•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. 

<img src='content_image/822126.jpg'>

## Note 

On systems that manage the server using systemd, mysqld_safe  is not available. Instead, specify the allocation library by setting LD_PRELOAD  in /etc/ sysconfig/mysql . 

Linux users can use the libtcmalloc_minimal.so  library on any platform for which a tcmalloc package is installed in /usr/lib  by adding these lines to the my.cnf  file: 

