How to change innodb_thread_concurrency in MySQL

I will give an example of changing innodb_thread_concurrency in MySQL.
Since InnoDB uses operating system threads to process user transactions, the innodb_thread_concurrency parameter allows you to limit them. By default in new MySQL versions the value is 0, which means that there is no limit on the number of simultaneously executed threads and this is correct for modern servers. If you want to limit, then when the limit is reached, the extra threads will wait a certain number of microseconds specified in the innodb_thread_sleep_delay parameter, and then try to get into the queue. Also in MySQL 5.6.3 and higher, the innodb_adaptive_max_sleep_delay parameter was added which allows you to specify the maximum number of microseconds for the innodb_thread_sleep_delay parameter and then InnoDB automatically adjusts innodb_thread_sleep_delay.

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FreeRadius. error solution rlm_sql_mysql: Couldn’t connect to MySQL server

Once I installed FreeRadius 3.0.23, by the way I described the process in the article: ABillS. Installing Freeradius, and optimized some parameters of the MySQL server, after which FreeRadius stopped starting and I saw errors in the logs:

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How to prevent Windows 10 from updating the driver

Once in one organization, old cash registers were used that were connected via COM port emulators and after automatic Windows updates, a new version of the COM port emulator driver was installed, after which it was displayed with an exclamation mark and stopped working, so it was necessary to prohibit the driver update.
Windows Pro and Enterprise have the ability to block driver updates through the Group Policy Editor (gpedit.msc). In this article I will show you how to do this.

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