… to use. Do push concurrency too high Many developers will test script with multiple level of concurrency and find out doing work… to serve other users too you typically need to reduce concurrency to where it does not overload the system. Unless it… a good idea. It also often helps with monopolizing replication thread. For example if I need to delete old data instead…
Post: Benchmarking single-row insert performance on Amazon EC2
May 16, 2012 By 11 Comments
…innodb_flush_method = O_DIRECT innodb_max_dirty_pages_pct = 50 innodb_io_capacity = 800 innodb_read_io_threads = 8 innodb_write_io_threads = 4 innodb…InnoDB, PARTITION p10 VALUES LESS THAN MAXVALUE ENGINE = InnoDB) */ Also, I ran 5 instances of iiBench simultaneously to simulate 5 concurrent…-set on…
Post: InnoDB's gap locks
March 27, 2012 By 15 Comments
… important features of InnoDB is the row level locking. This feature provides better concurrency under heavy …), undo log entries 1 MySQL thread id 3, OS thread handle 0x7f84a78ba700, query id 163 localhost …dev.mysql.com/doc/refman/5.1/en/innodb-locks-set.html. Conclusion MySQL uses REPEATABLE READ …
Post: Mess with innodb_thread_concurrency
May 12, 2006 By 1 Comment
… below 5.0.8 for unlimited threads you had to set innodb_thread_concurrency over 500 (and default value for innodb_thread_concurrency was 8 ). Starting with MySQL 5.0.8, the default value is 20, and concurrency…
Post: InnoDB thread concurrency
June 5, 2006 By 4 Comments
…thread->n_tickets_to_enter_innodb–; ENTER; } retry: if (entered_thread < innodb_thread_concurrency) { entered_threads++; thread->n_tickets_to_enter_innodb = innodb_concurrency_tickets; ENTER; } if (innodb_thread_sleep_delay > 0) { thread_sleep(innodb_thread…
Post: Tuning InnoDB Concurrency Tickets
May 24, 2010 By 4 Comments
… by innodb_thread_concurrency (which is why these two variables are most often tuned in concert). To continue the example, if innodb_thread_concurrency is set to…=2 innodb_log_file_size=1900M innodb_thread_concurrency=16 innodb_flush_method = O_DIRECT innodb_write_io_threads=8 innodb_read_io_threads=8 innodb_io_capacity=500 innodb_max…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 17 Comments
… the status of INNODB in 5.1.x? Specifically: What’s the current status of innodb_thread_concurrency ? Is it suggested to set this value to a LARGE value (somewhat like 200) for additional throughput? HT: ha_innodb.cc…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… size 320 MySQL thread id 30898, query id 100626 localhost root Updating update iz set pad=’a’ …Thread declared inside InnoDB 400″ means thread is running inside Innodb kernel and still has 400 tickets to use. Innodb tries to limit thread concurrency allowing only innodb_thread_concurrency threads…
Comment: Should MySQL update the default innodb_log_file_size?
November 24, 2011 By 37 Comments
…” “InnoDB: The combined size of ib_logfiles” ” should be bigger than\n” “InnoDB: 200 kB * innodb_thread_concurrency.\n” “InnoDB: To get mysqld to start up, set” ” innodb_thread_concurrency in my.cnf\n” “InnoDB: to a lower value…
Comment: kernel_mutex problem. Or double throughput with single variable
December 27, 2011 By 17 Comments
… 5.1 innodb_thread_concurrency the default value is 8 http://dev.mysql.com/doc/refman/5.1/en/innodb-parameters.html#sysvar_innodb_thread_concurrency 5…://dev.mysql.com/doc/refman/5.5/en/innodb-parameters.html#sysvar_innodb_thread_concurrency if we set innodb_thread_concurrency , the server ‘s load would get down…
