… staff, and especially the attendees for making last week’s conference a resounding success. …new development milestone release for MySQL 5.6, released on Monday. MySQL 5.6 just keeps looking better… Sheeri Cabral also recorded some of the breakout sessions, so watch Planet MySQL for an announcement…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking… Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take a look briefly at what… which range condition is applied cannot be used for filtering records. For example, suppose you have a key defined as: KEY…
Post: Multiple purge threads in Percona Server 5.1.56 and MySQL 5.6.2
May 3, 2011 By 13 Comments
… rid of–purge–the old versions of the records as they become obsolete. In MySQL 5.1 this is done by the master… parallelized purge: in MySQL 5.5 there is an option to have a single separate dedicated purge thread and in MySQL 5.6.2 one… the second half of the experiments is stable. Finally, the last two graphs: Again, we can see that there is no…
Post: Connecting orphaned .ibd files
May 13, 2011 By 12 Comments
…_actor_last_name (last_name) )ENGINE=InnoDB DEFAULT CHARSET=utf8; This command will create respective records in… 0x E4189B9B; recorded = 0x C168689B fixing new checksum of page 11 # # ./innochecksum -f /var/lib/mysql/ibdata1… The tool ibdconnect was tested on MySQL 5.1 on CentOS 5.6 x86_64. However …
Post: How InnoDB handles REDO logging
February 3, 2011 By 18 Comments
… MySQL configuration and hardware will affect the speed at which InnoDB can log. You can request that InnoDB force its REDO records…(s). How are the REDO records applied? InnoDB processes the REDO records from the last checkpoint, each record‘s LSN is compared against the… disk. Vadim touched upon this subject recently in his post MySQL 5.5.8 – in search of stability, as seen in his…
Post: Bug#12704861
November 20, 2011 By 1 Comment
… potentially be a very serious problem that is fixed in MySQL 5.1.60. I’ll repeat here the full documentation from… tell that crash recovery for updated records that contain BLOBs is broken in 5.1.58 and 5.1.59. Now, just because… where crash recovery will itself crash. The last sentence (“there is no redo log record for file extension in the current redo…
Post: How to recover deleted rows from an InnoDB Tablespace
February 20, 2012 By 3 Comments
…://dev.mysql.com/doc/refman/5.5/en/innodb-physical-record.html You can also get the table row format from the Information Schema: mysql… the data in our hands the last step is to import it in our database: mysql (employees) > LOAD DATA INFILE ‘/root/recovery… OK, 3 rows affected (0.01 sec) Records: 3 Deleted: 0 Skipped: 0 Warnings: 0 mysql (employees) > select * from salaries where emp…
Post: How is join_buffer_size allocated?
July 5, 2010 By 9 Comments
…examining MySQL configuration, we quite often want to know how various …5.1.47 source: 14176 /***************************************************************************** 14177 Fill join cache with packed records 14178 Records are stored in tab->cache.buffer and last record in 14179 last record…
Post: MySQL File System Fragmentation Benchmarks
March 21, 2008 By 28 Comments
… $i 10000000; mysql -e’drop database test1′; mysql -e’create database test1′; done; tables: 1; total records: 10000000; … is a lot of overhead. During this last test box felt really sluggish responding 10+ … some single value insert statements taking over 5 seconds… So it does not work very well….
Post: Dynamic row format for MEMORY tables
September 6, 2011 By 3 Comments
… HEAP) in MySQL has been one of the long-standing limitations caused by the fact that variable-length records were not supported by the engine. This is true for all MySQL versions, including the latest 5.6 development tree as of last… of eBay implemented true-VARCHAR support for MEMORY tables for MySQL 5.0. Although this patch did not add the BLOB and…
