…the combined size of the secondary key tuples fetched, and N is the buffer size. In MySQL 5.6 the buffer size used by MRR can be controlled by the…in the table above you can with default buffer size of 256K, MariaDB 5.5 shows that Handler_mrr_rowid_refills = 1, which means the…
Post: Time for Zero Administration effort at MySQL ?
January 8, 2012 By 4 Comments
…changing tables rather than command line options (like much of Performance Schema configuration). Innodb settings alone push 100. True you do…the same time however I am happy many more options got exposed over last few years. Majority of options in MySQL…MySQL would use the same sort_buffer_size…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…in mysql> show global variables like ‘%table_size%’; +———————+———–+ | Variable_name | Value | +———————+———–+ | max_heap_table_size | 268435456 | | tmp_table_size | 268435456 | +———————+———–+ If these are not the same size…
Post: Using MMM to ALTER huge tables
March 27, 2008 By 11 Comments
…you‘re altering gigabyte size tables…the “downtime” part. The longer it takes to apply application changes, the longer is the downtime. Our customer built his application so it automatically detects the…
Post: MySQL 5.5.8 - in search of stability
January 3, 2011 By 11 Comments
…in MB or GB and shows what amount of the space in innodb_log_file corresponds to changed pages in the buffer pool. You…the stable line in MySQL 5.5.8. But, finally, let me show the result I got running Percona Server in optimized mode: innodb_buffer_pool_size…
Post: High-Performance Click Analysis with MySQL
December 22, 2008 By 13 Comments
…you know you‘ll get there, it can change the lifecycle of your application in advance. What about partitioning in MySQL…the indexes less than half the size. In real life this technique often makes the table+index much less than half the size. You…
Post: New SpecJAppServer results at MySQL and Sun.
November 12, 2008 By Leave a Comment
…The MySQL Settings are probably what is the most interesting: MySQL 5.0 Tuning in /etc/my.cnf (included in…tables use in the benchmarks ? As otherwise you also need to boost tmp_table_size to deal with implicit memory tables. innodb_file_per_table…
Post: Innodb row size limitation
April 7, 2011 By 11 Comments
…in the original table. It also requires you to change the way you insert/modify data, as more tables are involved, and for example you…change the way your application uses this data. You can limit the changes to your application if you choose XML as format and you use MySQL‘s built in…
Post: Percona Toolkit 2.0.1 and 1.0.2 released
January 3, 2012 By 5 Comments
…MySQL administrators. There is one really big thing to talk about in this release: version 2.0 of pt-table-checksum. You know how you…you have to read the documentation on 99 command-line options to learn how to run the tool again in “show me the differences” mode, and if you…
Post: Recovering Innodb table Corruption
July 4, 2008 By 19 Comments
…MySQL server during query As you can see I can get rows from the table in the new one until we finally touch the row which crashes MySQL. In…how many rows do you need to skip exactly to recover as much data as possible. Row size can be good help to you. In…
