… seqrd (sequential read), seqwr (sequential write), rndrd (random read), rndwr (random write), rndrw (random read-write). And sysbench uses 16KB pagesize to emulate work of InnoDB with …consider RAID10 on 4 – 10 volumes. And of course to get benefit from multi-threading IO in MySQL you need to use …
Post: Choosing innodb_buffer_pool_size
November 3, 2007 By 39 Comments
…threads, temporary tables, per thread sort buffer which can be allocated. There are also things like innodb…Innodb Transactional Logs also like to be cached otherwise OS will need to do reads to serve writes to these log files as IO…
Post: InnoDB thread concurrency
June 5, 2006 By 4 Comments
… sequential read or random read); write_row; update_row; delete_row; At start of each of these methods InnoDB checks count of already entered threads, and… 2 active threads for each CPU and Disk resource. For Disk IO bound workload you could only account number of disks and for CPU…
Post: Reasons for MySQL Replication Lag
July 29, 2011 By 9 Comments
…write…and performance in general). Typical problems for replication include setting sync_binlog=1, enabling log_slave_updates, setting innodb…thread and…Read Traffic Changes Slave read traffic impacts replication performance dramatically and…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…IO helper threads – insert buffer thread, log thread, read thread and write thread. These are responsible appropriately for insert buffer merges, asynchronous log flushes, read-ahead and…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
…innodb_log_buffer_size = 8M innodb_buffer_pool_size = 128M innodb_log_file_size = 64M innodb_log_files_in_group = 2 innodb_read_io_threads = 8 innodb_write_io_threads = 8 innodb_io…bigger than 16G, I’ve repeated the random read (and write) benchmark with 8 threads and total size of 256G. While the …
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
…the reads and writes of mutex_t::waiters in mutex_get_waiters and mutex… between srv_monitor_thread and srv_error_monitor_thread InnoDB threads storing to srv…read of size 8 by thread #14 ==9090== at 0x6B0CAF2: buf_refresh_io_stats (buf0buf.c:3529) ==9090== by 0x6BC45D1: srv_error_monitor_thread…
Post: The relationship between Innodb Log checkpointing and dirty Buffer pool pages
February 17, 2012 By 10 Comments
… quickly starve data reads and writes to the transaction log if you set this too high. innodb_write_io_threads: Controls how many threads will have writes in progress… one thread (particularly if you have relatively few tables and/or use the global tablespaces) *cough ext3 cough*. innodb_adaptive_flushing: An Innodb plugin…
Post: MySQL 5.5.8 - in search of stability
January 3, 2011 By 11 Comments
…innodb_read_io_threads = 16 innodb_write_io_threads = 16 innodb_io_capacity=500 innodb_max_dirty_pages_pct = 60 innodb_purge_threads=1 innodb_adaptive_flushing=0 innodb_doublewrite=1 innodb_flush_neighbor_pages=0 innodb… innodb_max_dirty_pages_pct and innodb_io_capacity and having innodb_doublewrite…
Post: Tuning for heavy writing workloads
October 14, 2009 By 9 Comments
… innodb_io_capacity = 4000 innodb_support_xa = false innodb_file_per_table = true innodb_buffer_pool_size = 16G innodb_read_io_threads = 8 innodb_write_io_threads = 8 innodb_… master_thread (general background thread of InnoDB). The huge history list makes the purge operation slow, and it interferesÂ…
