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This article mainly introduces "what problems should be paid attention to when the Linux mysql dump guarantee program crashes". In the daily operation, I believe that many people have doubts about what problems should be paid attention to when the Linux mysql dump guarantee program crashes. The editor has consulted all kinds of materials and sorted out simple and easy-to-use methods of operation. I hope it will be helpful to answer the doubts of "which problems should be paid attention to when the Linux mysql dump guarantee program crashes". Next, please follow the editor to study!

Linux mysql dump should pay attention to these problems to ensure that Coredump is generated when the program crashes:

1. Linux mysql dump should ensure that the directory where the Coredump is stored exists and that the process has write permission to the directory. The directory where the Coredump is stored is the current directory of the process, which is usually the directory where the process was started when the command was issued. However, if you start through a script, the script may modify the current directory, and the real current directory of the process will be different from the directory in which the script was executed. At this point, you can look at the target of the "/ proc//cwd" symbolic link to determine the real current directory address of the process. Processes started by system services can also be viewed in this way.

2. Linux mysql dump if the program calls seteuid () / setegid () to change the valid user or group of the process, the system will not generate Coredump for these processes by default. Many services call seteuid (), such as MySQL, and no matter what user you use to run mysqld_safe to start MySQL,mysqld, the valid user is always the msyql user. If you run a program as user A, but the user of the program you see in ps is B, then these processes are calling seteuid. In order for these processes to generate core dump, you need to change the contents of the / proc/sys/fs / suid_dumpable file to 1 (the default is generally 0).

Third, Linux mysql dump generally knows that it is necessary to set a Core file size limit that is large enough. The size of the Core file generated when the program crashes is the amount of memory consumed when the program is running. However, the behavior of a program when it crashes can not be estimated according to its normal behavior, such as buffer overflow and other errors may cause the stack to be destroyed, so it is common for the value of a variable to be modified into a mess. then the program uses this size to request memory, which may cause the program to take up more memory than usual. Therefore, no matter how little memory is used when the program is running normally, it is better to make sure that the Core file is generated and the size limit is set to unlimited.

At this point, the study on "what problems should be paid attention to when the Linux mysql dump guarantee program crashes" is over. I hope to be able to solve everyone's doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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