…Lock_time: 0.000048 Rows_sent: 56 Rows_examined: 1113 LOGGING OF THE REPLICATED STATEMENTS Normally MySQL…indexes. If a temporary table is required for query execution Tmp_table will be set. Sometimes that table must be created… page read operations scheduled. The acutal number of read operations may…
Post: The new cool MySQL patch has landed! Check your queries performance!
October 31, 2007 By 16 Comments
Post: How much memory Innodb locks really take ?
July 13, 2006 By 11 Comments
… 0 Index_length: 128974848 Data_free: 0 Auto_increment: 1638401 Create_…locked row; Now lets see how much exclusinve locks take: mysql> begin; Query OK, 0 rows affected (0.00 sec) mysql…read mode which does not set any locks is going to be faster than any of locking modes, however we can see locking…
Post: Another scalability fix in XtraDB
January 23, 2009 By 13 Comments
…default ’0′, PRIMARY KEY (id) ) CREATE INDEX email_idx on sbtest(email); CREATE INDEX country_id_idx on sbtest(…after 8 connections, si I decided to test MySQL-5.1.30 with standard InnoDB. It was…where shared read lock is enough – and we replaced page_hash mutex to page_hash read-write lock. The …
Post: Announcing Percona Server 5.1.66-14.2
January 15, 2013 By Leave a Comment
…Software Repositories). Based on MySQL 5.1.66, …fixed #1083377 (Vlad Lesin). Rows_read was calculated in …row locks to shared (S) locks, these S locks prevent X locks …1076892 (Laurynas Biveinis). Temporary files created by binary log …(Alexey Kopytov). In cases where indexes with AUTO_INCREMENT columns…
Post: MySQL Slow query log in the table
May 31, 2007 By 1 Comment
…MySQL 5.1 get MySQL slow query log logged in mysql…. query execution time and lock time does not store fractions…indexes may be significant overhead, so you can instead create analyze_low_log table of similar structure with needed index…do any write queries) only read access is possible, with exception…
Post: MySQL 5.6: Improvements in the Nutshell
January 27, 2013 By 16 Comments
…MySQL University in Raleigh,NC, Tuesday 29th of January I have created the outline of improvements available in MySQL… Fragmentation – Reduced Locking for Partitioned tables – Reduced Contention for LOCK_open – … Optimizer and Execution – Index Condition pushdown (ICP) – Multi-Range-Read (MRR) – …
Post: Thinking about running OPTIMIZE on your Innodb Table ? Stop!
December 9, 2010 By 18 Comments
… 2 rows in set (4 min 5.52 sec) mysql> alter table a add key(c); Query…LOCK TABLES on Innodb table to ensure there is not ton of queries starting reading table with no indexes…this was not done when support for creating index by sorting was implemented. It looks …
Post: MySQL Error Message Nonsenses
March 16, 2008 By 7 Comments
… operation could not be performed (read error, out of file descriptors etc…: Wrong medium type MySQL error code 124: Wrong index given to function …1005 at line 20: Can’t create table ‘./test/test.frm’ (errno: 150…transactional storage engines we surely saw lock related tables being far from consistent…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…index scans more efficient. I can’t wait for ability to create physically sorted indexes with Innodb (with index…to schedule sequential read-ahead, random read ahead ? HT: InnoDB schedules a sequential read-ahead when … global MySQL Server option, though it may have problems on Linux if you lock very …
Post: The perils of InnoDB with Debian and startup scripts
January 28, 2009 By 13 Comments
… for 0.00 seconds the semaphore: S-lock on RW-latch at 0x2aaaae0b70b8 created in file btr0sea.c line 139 a writer… for 0.00 seconds the semaphore: S-lock on RW-latch at 0x2aaaae0b70b8 created in file btr0sea.c line 139 a writer…, OS thread id 1159956816 starting index read, thread declared inside InnoDB 500 mysql tables in use 7, locked 0 MySQL thread id 6424, query id…
