… from SHOW INNODB STATUS mean? Mutex spin waits 5870888, rounds 19812448, OS waits 375285 To understand this text, you have to understand how InnoDB handles mutexes. It… it waited in a spin-wait. rounds 19812448 is the number of times threads looped in the spin-wait cycle, checking the mutex. OS waits 375285…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… flag 0 wait is ending Mutex spin waits 5672442, rounds 3899888, OS waits 4719 RW-shared spins 5920, OS waits 2918; RW-excl spins 3463, OS waits 3163 There… with which Innodb needs to fall back to OS Wait. There is direct information about OS waits as well – you can see “OS Waits” for mutexes, as well…
Post: The perils of InnoDB with Debian and startup scripts
January 28, 2009 By 13 Comments
…Mutex spin waits 0, rounds 5023577, OS waits 24953 RW-shared spins 34364070, OS waits 33800501; RW-excl spins 5756394, OS waits 5297208 Everyone is waiting for mutexes…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
…-5.1.61) and a single test, innodb_plugin.innodb_bug53674. The test is chosen for no …size 8 by thread #1 ==9090== at 0x6BC9FFF: mutex_spin_wait (sync0sync.c:441) ==9090== by 0x6B751FC: mtr… 0x6e26200 by thread #1 ==9090== at 0x6B77778: os_file_write (os0file.c:2172) ==9090== by 0x6B35B5E…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 17 Comments
…InnoDB has to wait. PZ: This one is a bummer. I thought Innodb will make sure to schedule synchronous wait…OS may swap out not buffer pool but some other important parts of MySQL process. Q20: We’ve migrated to using INNODB… binlog write and the InnoDB log flush with a mutex in 5.1, to implement…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…Innodb_buffer_pool_wait_freeblogpercona.commanual Innodb_buffer_pool_write_requestsblogpercona.commanual innodb_change_bufferingblogpercona.commanual innodb_checksumsblogpercona.commanual innodb_commit_concurrencyblogpercona.commanual innodb_concurrency_ticketsblogpercona.commanual innodb…
Post: Scaling problems still exist in MySQL 5.5 and Percona Server 5.5
May 20, 2011 By 11 Comments
… pthread_cond_wait,os_cond_wait,os_event_wait_low,sync_array_wait_event,mutex_spin_wait,mutex_enter_func,pfs_mute x_enter_func,buf_page_get_mutex_enter… index makes things a lot worse in this workload and innodb_adaptive_hash_index_partitions=16 available for partitioning adaptive hash…
Comment: Returning to InnoDB scalability
August 4, 2006 By 42 Comments
…MUTEX STATUS output , here you go :: mysql> SHOW MUTEX STATUS ; +—————————+————-+————–+————+————-+———-+———–+—————+ | Mutex | Module | Count | Spin_waits | Spin_rounds | OS_waits | OS_yields | OS_waits…
Comment: Returning to InnoDB scalability
September 13, 2006 By 42 Comments
…waits | Spin_rounds | OS_waits | OS_yields | OS_waits_time | +——————————–+————-+————–+————+————-+———-+———–+—————+ | &(trx->undo_mutex) | trx0trx.c | 11097787 | 0 | 0 | 0 | 0 | 0 | | &(table->autoinc_mutex…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
… How many read-aheads can be waiting in Queue when or Innodb will schedule more read-aheads only…the good way to split memory between INNODB buffers and OS?†Of course this depends on …operations for different levels of concurrency, specifically around mutexes and contention? How does this fit into …
