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Linux Find Out CPU Architecture Information

How do I find out my CPU architecture information under Linux operating systems?
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[ERROR] /usr/local/libexec/mysqld: unknown variable ‘thread_concurrency=8’

I'm trying to set 'thread_concurrency to 8 under Linux MySQL server. But when I try to restart the mysql server, I get the following error:

[ERROR] /usr/local/libexec/mysqld: unknown variable 'thread_concurrency=8'

How do I fix this problem?
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MySQL: Find Out Which Table is Consuming Resources

Q. How do I find out which table is consuming resources under MySQL Database server from UNIX shell prompt?
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Linux nice command: Run Process With Modified Scheduling Priority ( nicenesses )

Q. How do I run a process with modified scheduling priority under Linux? I'd like to change the priority in the kernel's scheduler while starting a command.

A. Use nice command to run a program with modified scheduling priority / nicenesses. Nicenesses range at least from -20 (resulting in the most favorable scheduling) through 19 (the least favorable). The default behavior is to increase the niceness by 10.

A niceness should not be confused with a scheduling priority, which lets applications determine the order in which threads are scheduled to run. Unlike a priority, a niceness is merely advice to the scheduler, which the scheduler is free to ignore.

nice syntax (/bin/nice command)

/bin/nice -n NUM

Add integer NUM (-20 to 19) to the niceness.

WARNING! There are multiple versions of the nice command. One built in to the shell, and one in /bin/nice. The syntax may be diffrent on your system. Refer your shell and /bin/nice command man page for details.

Change niceness by 3

Type the command as follows:
$ /bin/nice -n 3 command-name

Only a privileged user may run a process with lower niceness:
$ /bin/nice -n -1 command-name

Shell in build nice command syntax

If you use the csh or tcsh or bash, the syntax is as follows:
nice +n command
I recommend using /bin/nice syntax to avoid confusion and to save time.