mySQL and more CPUs

by | Nov 20, 2015 | Settings |

  • there are misunderstatements about multicore usage per query or per server
  • per server:
    • multiple threaths can handle I/O operations
    • InnoDB 5.7 should be able to scale up to 60 cores, in 5.1 it was max 8 cores
    • parameters:
      • innodb_concurrency_tickets
      • innodb_thread_sleep_delay
      • innodb_read_io_threads
      • innodb_write_io_threads
      • innodb_thread_concurrency (should be set to 0 to allow engine find optimum)
  • per query:
    • one query can use only one core – multicore usage requires parallel execution plan and transparent data spliting between cores which is possible only in some other databases