::: ZOSEL ::: :: Mysql Thread Pool

MySQL 5.6 Enterprise 버젼에 있는 것이 Thread Pool 입니다.

기존의 단선적인 Thread 관리를 효율적으로 해주는 것으로 부하가 심한 DB에 유용하죠.

그런데... Enterprise 버젼의 1년 이용료가 무려 $5,000... ㄷㄷㄷ...

그래서 찾아보니 Maria DB는 Thread Pool 기능이 오래전에 들어가 있었네요.

Plugin이 아니마 built-in 입니다.

https://kb.askmonty.org/en/threadpool-in-55/

Commercial editions of MySQL since 5.5 include an Oracle MySQL Enterprise threadpool implemented as a plugin, which delivers similar functionality. Official documentation of the feature can be found in the MySQL Reference Manual and a detailed discussion about the design of the feature is at Mikael Ronstrom's blog. Here is the summary of similarities and differences, based on the above materials.

Similarities

On Unix, both MariaDB and Oracle MySQL Enterprise Threadpool will partition client connections into groups. The thread_pool_size parameter thus has the same meaning for both MySQL and MariaDB.

Both implementations use similar schema checking for thread stalls, and both have the same parameter name for thread_pool_stall_limit (though in MariaDB it is measured using millisecond units, not 10ms units like in Oracle MySQL).

Differences

The Windows implementation is completely different ? MariaDB's uses native Windows threadpooling, while Oracle's implementation includes a convenience function WSAPoll() (provided for convenience to port Unix applications). As a consequence of relying on WSAPoll(), Oracle's implementation will not work with named pipes and shared memory connections.

MariaDB uses the most efficient I/O multiplexing facilities for each operating system: Windows (the I/O completion port is used internally by the native threadpool), Linux (epoll), Solaris (event ports), FreeBSD and OSX (kevent). Oracle uses optimized I/O multiplexing only on Linux, with epoll, and uses poll() otherwise.