…Tables MEMORY tables can take memory. There are implicit MEMORY tables which are allocated for query execution, which size can be controlled by tmp_table_size and which…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… on TPC-H dataset (InnoDB tables) with a Scale Factor of 2 (InnoDB dataset size ~5G). Note … high numbers of Innodb_buffer_pool_read_ahead when the buffers are sized appropriately, which shows that …buffers indirectly impact BKA performance. I did not find much of a performance improvement from using …
Comment: How FLUSH TABLES WITH READ LOCK works with Innodb Tables
March 26, 2012 By 20 Comments
… a method that is derived from that. Essentially, we are using FLUSH TABLES WITH READ LOCK, and then run ‘lvcreate -s’ to… the target location, we bring up the new mysqld, which finds a crashed innodb, recovers this, and then it is being configured to… recovery of the innodb in the target location fails, though, even though it has been made even under FLUSH TABLES WITH READ…
Comment: How FLUSH TABLES WITH READ LOCK works with Innodb Tables
March 26, 2012 By 20 Comments
…find the bug if it is the bug or user error. I think the innodb data from the backup where Innodb…Innodb itself or how XFS plays with LVM or something. As mark mentions – indeed there are known problems which are not handled if you have DDL however FLUSH TABLES…
Comment: Percona Toolkit 2.1 with New Online Schema Change Tool
April 22, 2012 By 9 Comments
…2. Secondly, I read here that you are the lead author of High Performance … MySQL” by Jeremy Zawodny & Derek Balling (which I own, but is outdated as…avalable on DotDeb.org, and I find my qps dropping by 2/3 -… everyone? Have some updates made to INNOdb tables really slowed down mySQL as measured …
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… to be investigated. You might find that there are InnoDB tables whose .frm files exist but have been dropped from InnoDB, for example. (The INFORMATION… desired information about the queries by any means necessary, I find out which are the most likely to give the greatest gains. I…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…are same as you previously could find in SHOW INNODB STATUS, there are however few which were not available before. In SHOW INNODB STATUS many values are…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
…them are Innodb specific and it well can affect your workload. So benchmark to be sure. In Innodb … us greatly to spot scalability problems and find fixes for them. The work continues. I … reorganize which locks and reorganizes small portions of table online. Q38: Seems that adaptive hash indexes are …
Post: Recovering Innodb table Corruption
July 4, 2008 By 19 Comments
… checksum failing CHECK TABLE says table is OK. This means You Can’t Trust CHECK TABLE in Innodb to be sure your tables are good. In this simple corruption was only in the data portion of pages so once you started Innodb with innodb_force… in the table and we need to somehow skip over it. To do it we would need to find max PK which could…
Post: Innodb Recovery Update - The tricks what failed.
May 24, 2007 By 3 Comments
….0.33 are not frequently used True many distributions still have versions before this one which could have some impact. Innodb tables rarely become corrupt Indeed even if you leave out crashes in my experience Innodb tables become… probably report half of the bugs I find, the once I find most annoying or find easy to provide repeatable example for so…
