… with MySQL is what they happen every so often or certain times. Investigating them we find out what … resources. Here are some specific techniques to use. Do push concurrency too high Many developers …It also often helps with monopolizing replication thread. For example if I need to delete old …
Post: Zero-Downtime Schema Changes In MySQL
May 3, 2012 By 2 Comments
… defeat the purpose of the tool. Q: When you say bail out, what does that…It is designed to be resumable, although we don’t yet have a “resume” feature…MySQL bug. Are you sure this is really happening? I would be extremely surprised for… binary logging at all. Are you using the 2.0 version of this tool…
Post: Benchmarking single-row insert performance on Amazon EC2
May 16, 2012 By 11 Comments
…for which this tool was originally built is long over, but still the tool serves well for benchmark purposes…MySQL configuration. MySQL Configuration I used Percona Server 5.5.22-55 for the tests. Following is the configuration that I used…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
… uses MySQL to identify potential causes. Is it working with large blobs ? Using user variables…We can look at information_schema to see how much memory is being used by current MEMORY tables: mysql…MySQL, MariaDB or Drizzle bring improvements in this space allowing us to see directly for what purpose…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
…MySQL 5.6 and MariaDB 5.5 Now let’s take a look at what this optimization actually is and what…MySQL 5.6) mrr_buffer_size=4M (only on MariaDB 5.5) We have turned off ICP optimization for the purpose…4 NULL 232722 100.00 Using where; Rowid-ordered scan; Using temporary; Using filesort 1 SIMPLE customer…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… Key Access Traditionally, MySQL always uses Nested Loop Join to join two or more tables. What this means is…difference in numbers. Benchmark results For the purpose of this benchmark, I have used TPC-H Query #3 … numbers are values for Innodb_buffer_pool_reads and Innodb_data_read. We can see that …
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 …MySQL 5.6 and MariaDB 5.5 Now let’s take a look briefly at what this enhancement actually is, and what… range condition is applied cannot be used for filtering records. For example, suppose you have a key …
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 8 Comments
…MySQL monitoring plugins we created for Nagios, and explain their features and intended purpose. I want to add a little context. What problem were we… extensive list of suggestions for what to monitor in MySQL. Those are only … careful configuration because it uses a threshold for which there is no…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
… it’s a shame. What I have to found to be useful in the daily work …MTR we are talking about. For a proper implementation for our purposes, Patrick has added preliminary Helgrind support to DBQP. For… using MySQL 5.5 atomic operation primitives with proper memory barriers, so that there is no need for…
Post: Using Flexviews - part two, change data capture
March 25, 2011 By 11 Comments
…what rows have changed. Because of this, FlexCDC requires that you use row-based binary logs (RBR). If you don’t have MySQL…filename to search for. I included it in the earlier examples for illustration purposes. Examine the …, each representing one of the changes we made. You will notice that the …
