… OS may swap out not buffer pool but some other important parts of MySQL process. Q20: We’ve migrated to using INNODB… good performance is to set innodb_flush_log_at_trx_commit=2, that is, to flush the log to the disk only once… so. Sergei Golubchik serialized the MySQL binlog write and the InnoDB log flush with a mutex in 5.1, to implement XA…
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
… estimates. If we’re running Innodb with MySQL we can use Innodb_data_reads , Innodb_data_writes, Innodb_os_log_fsyncs for your disk IO estimation… 14 783 158.14 621.67 149.04 107.34 # InnoDB: # IO r bytes 14.81G 0 1.10G 8.69k… 0 0 0 0 0 0 # String: # Databases # Hosts localhost # InnoDB trxID 3BBF3B55 (1/0%), 3BBF3B5A (1/0%)… 1753695 more # Last…
Post: Innodb usability and ease of use.
September 28, 2007 By 14 Comments
… less understandable with value 0 meaning disabling Innodb internal thread queuing. Another one is innodb_flush_logs_at_trx_commit – initially it had… your my.cnf file – For example using values “none”, “disk”, “os” instead of 0,1,2 will be more explanatory. Furthermore… and 1. Interesting enough in some cases Innodb team does get things right. innodb_flush_method variable does not use value 0…
Comment: Measuring the amount of writes in InnoDB redo logs
October 9, 2012 By 4 Comments
Hi Stephane, I noticed that difference too between LSN & Innodb_os_log_written but didn’t succeed to explain it, thanks for the explanations !
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
… not forget you may need to increase size of your Innodb log files to be able to use a lot of memory… solid state disks for storing ib_log* files; I know that innodb writes files in the log file group in a round robin…€œWhat is the good way to split memory between INNODB buffers and OS?†Of course this depends on all kinds of…
Comment: table_cache negative scalability
April 14, 2010 By 23 Comments
…/panel_decert.frm’ (errno: 24) [root@wcdb /db]# perror 24 OS error code 24: Too many open files I have this… = MYISAM log_long_format # Innodb innodb_status_file = 1 innodb_file_per_table = 1 innodb_data_home_dir = /db2/innodb innodb_log_group_home_dir = /db-logs/ibdlogs innodb_data_file_path = ibdata1:10M:autoextend innodb_buffer_pool_size = 30G innodb_log_buffer_size = 8M innodb_additional…
Post: What to tune in MySQL Server after installation
September 29, 2006 By 118 Comments
… larger) so you can see how much memory Innodb allocates for misc needs. innodb_log_file_size Very important for write intensive workloads… enough. Smaller installations should use smaller values. innodb_flush_log_at_trx_commit Crying about Innodb being 100 times slower than MyISAM ? You… Server crashes. Value 2 only cause data loss with full OS crash. table_cache – Opening tables can be expensive. For example…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
…-server Architecture | CPU = 64-bit, OS = 64-bit # Processor ################################################## Processors | physical = 2,…innodb_flush_log_at_trx_commit = 2 innodb_flush_method = O_DIRECT innodb_log_buffer_size = 8M innodb_buffer_pool_size = 128M innodb_log_file_size = 64M innodb_log…
Post: InnoDB memory usage
May 30, 2006 By 8 Comments
… another calculation for OS_THREADS) So InnoDB uses: innodb_buffer_pool innodb_additional_mem_pool_size innodb_log_buffer_size adaptive index hash, size= innodb_buffer_pool… final formula for innodb: innodb_buffer_pool_size + innodb_log_buffer_size + innodb_additional_mem_pool_size + 812 / 16384 * innodb_buffer_pool_size + OS_THREADS * 368 For…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
… version (pre-5.1.61) and a single test, innodb_plugin.innodb_bug53674. The test is chosen for no particular reason except… read of size 8 by thread #14 ==9090== at 0x6B79F6F: os_aio_refresh_stats (os0file.c:4408) ==9090== by 0x6BC459F: srv… issues, show similar issues (other InnoDB stat counters), show non-issues or my analysis errors (like the log_sys->lsn “race” above…
