…_ind` tuple: DATA TUPLE: 2 fields; 0: len 4; hex 80000002; asc ;; 1: len 6; hex 000000000401; asc ;; But in parent table… 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 to run inside Innodb kernel at the same time. If thread is not runniing inside…
Post: MyISAM Scalability and Innodb, Falcon Benchmarks
October 12, 2007 By 10 Comments
… run on 4 Core System: Threads queries/sec 1 161 2 107 4 110 8 121 16 138 As you see running 2-4 threads concurrently we get result by 30% worse than with 1 thread, although… less than 2x in peak which happens to be at 4 concurrent threads. So there is still work to do in addition to…
Post: kernel_mutex problem cont. Or triple your throughput
December 2, 2011 By 10 Comments
…_thread_concurrency=8. So now let’s compare results for innodb_thread_concurrency= 0 vs 8 for all range of threads: Threads innodb concurrency=0 innodb concurrency=8 1 11178.34 2 27741.06 4 53364.52…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…changed mysql> show table status like ‘ontime_fact’G *************************** 1. row *************************** Name: ontime_fact Engine: InnoDB Version: 10…-thread-concurrency=0 innodb-thread-concurrency-timer-based innodb-thread-sleep-delay=0 innodb-use-sys-stats-table innodb-write-io-threads=4…
Post: kernel_mutex problem. Or double throughput with single variable
December 2, 2011 By 17 Comments
… result for different threads (against Percona Server 5.5.17): Threads Throughput, q/s 1 11178.34 2 27741.06 4 53364.52 8…_loops=200 for 1-1024 threads. Threads Throughput Throughput spin 200 1 11178.34 11288.42 2 27741.06 28387.62 4 53364.52 53575… problem. Further direction I want to try to limit innodb_thread_concurrency and also bind mysqld to less CPUs, and also it…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
… the aio read thread. Thus, about 4 readaheads can be in the queue at a time. The read aio thread will normally read… of concurrent writes to about 6 tables, what version of Innodb/MySQL would you recommend? I’ve been staying at 4.1.14… levels of concurrency, specifically around mutexes and contention? How does this fit into the development process? HT: Contention and thread thrashing depends…
Post: Why do we care about MySQL Performance at High Concurrency?
February 26, 2013 By 9 Comments
… concurrency. In some cases reaching 4,000 or more concurrent threads which hammer databases as quickly as possible resulting in hundreds or even thousands concurrently… has just 1/4th of its Peak performance of concurrency of 1000 while Red Line of MySQL Enterprise Edition with Thread Pool plugin…
Comment: MySQL on Amazon RDS part 2: Determining Peak Throughput
March 28, 2011 By 4 Comments
…_lock_mode 1 innodb_buffer_pool_size 55050240000 innodb_change_buffering inserts innodb_checksums ON innodb_commit_concurrency 0 innodb_concurrency_tickets 500…_locks ON innodb_thread_concurrency 0 innodb_thread_sleep_delay 10000 innodb_use_sys_malloc ON innodb_version 1.0.11 innodb_write_io_threads 4
Comment: MySQL Server Memory Usage
September 1, 2006 By 21 Comments
…’ ‘Threads_cached’, ’0′ ‘Threads_connected’, ’260′ ‘Threads_created’, ’124272′ ‘Threads_running’, ’3′ ‘Uptime’, ’4433556′ # top 18:38:40 up 175 days, 2:56, 1 user….0% 0.3% 6.5% 68.4% cpu00 22.1% 0.0% 11.1% 0.1% 1.1% 6.1% 59.1% cpu01 14.9% 0.0% 7…_log_file_size=400M # Approx 20% of buffer pool innodb_thread_concurrency=64 # Default is 8 wich is a way to low…
Comment: InnoDB thread concurrency
March 19, 2012 By 4 Comments
…thread) I/O thread 1 (thread id: 18579) state: waiting for completed aio requests (log thread) I/O thread 2 (thread…thread 9 (thread id: 18587) state: waiting for completed aio requests (write thread) but i found that the value of the innodb_thread_concurrency…
