…slow (when the FS cache is cold, IO to slow …INNODB_BUFFER_POOL_READS | 191571 | | INNODB_DATA_PENDING_READS | 0 | | INNODB_DATA_READ | 3140882432 | | INNODB_DATA_READS | 191581 | | INNODB_PAGES_READ | 191570 | | INNODB…D_WeekDayFl tinyint ); DROP TABLE IF EXISTS lineorder; CREATE TABLE IF NOT EXISTS…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… be an indication that it’s time to convert MyISAM tables to InnoDB. (But then again, it might not be.) Or maybe…. You might find that there are InnoDB tables whose .frm files exist but have been dropped from InnoDB, for example. (The INFORMATION_SCHEMA query…: wget http://hackmysql.com/scripts/mysqlsla perl mysqlsla -lt slow /path/to/slow.log By default, this outputs the top 10 most…
Post: Implications of Metadata Locking Changes in MySQL 5.5
February 1, 2013 By 9 Comments
…end | 0.000002 | | closing tables | 0.000003 | | freeing items | 0.000007 | | logging slow query | 0.000002 | | …InnoDB; However, I feel that the CREATE TABLE should fail in such a case when the table already exists and there is no other DDL like a DROP table waiting to run on the same table…
Post: Improved InnoDB fast index creation
November 6, 2011 By 4 Comments
… tmpdir. The constant “copying to tmp table” part will not be affected by a slow tmpdir, but rebuilding the indexes will obviously… avoid dropping keys that are part of a FOREIGN KEY constraint; mysqldump –innodb-optimize-keys ignores foreign keys because InnoDB requires a full table…
Post: Announcing Percona Server for MySQL version 5.5.29-30.0
February 26, 2013 By Leave a Comment
… Bug fixed #1083058 (Laurynas Biveinis). Upstream changes made to improve InnoDB DROP TABLE performance were not adjusted for XtraDB. This could cause …fixed #730173 (Laurynas Biveinis). Fixed the incorrect help text for slow_query_log_timestamp_precision. Bug fixed #1090965 (Laurynas Biveinis). …
Post: Thinking about running OPTIMIZE on your Innodb Table ? Stop!
December 9, 2010 By 18 Comments
… using LOCK TABLES on Innodb table to ensure there is not ton of queries starting reading table with no indexes and bringing box down. You can also use this trick for ALTER TABLE which requires table rebuild. Dropping…get advantage of it and will use old slow method of building indexes by…
Post: Why MySQL could be slow with large tables ?
June 9, 2006 By 141 Comments
…drop in performance. This especially apples to index lookus and joins which we cover later. As everything usually slows…. There are also clustered keys in Innodb which combine index access with data …tables being small it would not slow things down too much. On other hand join of few large tables…
Post: MySQL 5.5 and MySQL 5.6 default variable values differences
February 21, 2013 By 8 Comments
… | 2000 | | INNODB_VERSION | 5.5.30 | 1.2.10 | | INNODB_BUFFER_POOL_INSTANCES | 1 | 8 | | QUERY_CACHE_SIZE | 0 | 1048576 | | SLOW_QUERY_LOG… which is good change as trying to create Innodb table but getting MyISAM because Innodb was disabled for some reason was very error… been when you have large number of tables or if you do many create/drop of innodb tables. optimizer_switch is the catch all…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
…or can a bit slow it down. Plus there were bunch of micro optimizations in Innodb in 5.0 … of RAM used for these non-mysql processes drops rapidly when you increase the amount of system … up in “show innodb statusâ€. select * from table where id=5 show innodb status: Hash table size 10624987, used …
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
… big tables, a secondary index reserves different extents from the clustered index. Q4: Does Innodb …the pessimistic delete, if the page data size drops below this limit, merging it to …slows down throughput. If we could control the checkpointing rate we could use an 8G write ahead log and tell innodb…
