…mode. There are two reasons for that. First, MySQL/InnoDB uses async writes, so this will emulate database…level. I really thought that these stalls are related, so I was totally surprised them in … about drops – the drive periodically cleans an internal cache or something. To understand better what …
Post: Testing STEC SSD MACH16 200GB SLC
April 25, 2012 By 7 Comments
… use sysbench fileio, 16KiB block size (to match workload from InnoDB, as this is primary usage for me), and recently I… async IO mode. There are two reasons for that. First, MySQL/InnoDB uses async writes, so this will emulate database load, and… small drop to 87 MiB/sec, which I guess is related to internal garbage collector activity. The results for random read case…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…MySQL is troubleshooting memory usage. The problem usually starts like this – you have configured MySQL to use reasonable global buffers, such as innodb… Table Cache Related Allocations There are cases when MySQL will …; in additional pool allocated 0 Internal hash tables (constant factor + variable…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… info to improve MySQL Performance. To start with basics SHOW INNODB STATUS is command which prints out a lot of internal Innodb performance counters, statistics, information about transaction processing and all kinds of other things. In MySQL 5 number of Innodb performance… tablespace related IO from log related IO so you can see how much IO your log file requires. Note depending on your innodb…
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
…queries per second on such system. There are internal scaling aspect of the system which include … If we’re running Innodb with MySQL we can use Innodb_data_reads , Innodb_data_writes, Innodb_os_log_fsyncs for…full you can also get great amount of related data from mk-query-digest report: # Overall: 1…
Post: Distributed Set Processing with Shard-Query
May 14, 2011 By 27 Comments
…relational algebra expresion. Relational algebra expressions always produce sets as output. Just to drive it home, SQL is relational… the final result set. Intern-node communication One …but right now only MySQL storage nodes are supported… computation over ICE, InnoDB, Vectorwise and other databases,…
Post: MySQL Error Message Nonsenses
March 16, 2008 By 7 Comments
… MySQL error code 150: Foreign key constraint is incorrectly formed What is also interesting is – this error 150 is in fact internal Innodb… we surely saw lock related tables being far from consistent. Let me give you another example. So Innodb has limit of 1023… error is foreign key related but you also need to run SHOW INNODB STATUS to see what exactly Innodb did not like about…
Post: MySQL Crash Recovery
July 30, 2006 By 26 Comments
… or .frm being unsync with internal Innodb dictionary may cause MySQL to fail with wierd error messages. In MySQL 4.1 sync_frm option… other problems which you may experience related to MySQL Crash Recovery – Restoring data from backup, corrupted Innodb tablespace recovery etc but I should…
Comment: 7 Reasons why MySQL Quality will never be the same
December 11, 2008 By 15 Comments
…when they do, they must work. Many recovery-related bugs are not easily reproducible and it … users on the InnoDB forums. Most of the bugs were found through extensive internal testing. And, …/MySQL engineers to maintain the reliability of InnoDB as distributed by MySQL as well as in the InnoDB Plugin…
Page: Presentations
May 3, 2006 By
… 2007 Presentation about Sphinx, the tasks it solves, internals and examples of usage Download Hg – Mercurial Egypt,…MySQL as well as solve other performance related problems. Download Innodb Performance Optimization MySQL Users Conference 2007, Santa Clara,CA, April 2007 Presentation covering Innodb…
