… Database Service (RDS) is a cloud-hosted MySQL solution. I’ve had some clients hitting …-threaded insert workload is not very revealing. To understand the sustained write performance of an RDS instance…have published this result without being able to explain exactly what was happening on the server. …
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…mysql –user=mysql –pid-file=/var/run/mysqld/mysqld.pid –skip-external-locking –port=3306 –socket=/var/db/mysql/mysql…t understand what I’m doing, I’ve done something wrong. Clients need to understand so…etc), the EXPLAIN plan, and the desired modifications to the query or the table. We explain …
Post: Find unused indexes
June 30, 2012 By Leave a Comment
… adds some tables to Information Schema with useful information to understand the server activity and identify the source of the load… is easy to understand. pt-index-usage reads the slow query log and execute every query with EXPLAIN to ask MySQL which indexes… index. So we’re comparing an estimation with real data. EXPLAIN, as I said before, is an estimation from the optimizer…
Post: 3 ways MySQL uses indexes
September 12, 2009 By 28 Comments
… of this mistakes come from missing one very important MySQL limitation – once MySQL runs into the interval range it will not use…” type in explain which correspond to scanning (potentially) complete table in the index order. It is very important to understand in which… in memory. If MySQL is only reading index and not accessing rows you will see “using index” in EXPLAIN output. These are…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
…, not just for new connections as in MySQL. This is very helpful for measurement as …95th percentile) column as that gives us more accurate understanding. Now, for example it is shown here … CREATE TABLE `wp_blog_one `.`wp_options`\G # EXPLAIN /*!50100 PARTITIONS*/ SELECT option_name, option_value …
Post: MySQL Support or Support for MySQL ? MySQL Trademark Policies
October 26, 2007 By 11 Comments
… it because MySQL contacted me about our consulting company new “corporate” site and rename Services appropriately. As Monty explained me once MySQL has… secured permission from MySQL these products can be at risk and MySQL may request them to be renamed. As I understand what you…
Post: MySQL 5.5.8 - in search of stability
January 3, 2011 By 11 Comments
… article, and I strongly recommend reading if you want to understand how InnoDB works. In his post, Dimitri questioned some of…_start localhost tpcc500w root “” 500 32 10 1800. For better understanding the results for each run, I will show different graphs…, the results for the initial run, using MySQL 5.5.8: Let me explain the second graph a little. I put…
Post: How we work on High Performance MySQL Second Edition
November 12, 2007 By 12 Comments
… being involved in MySQL Support, MySQL Consulting, Documentation, MySQL Training while working for MySQL and now on…which were often very explanatory easy to understand and full with examples. They also were…different backgrounds both to fix mistakes and explain things which are not clear enough. …
Post: Database problems in MySQL/PHP Applications
August 11, 2006 By 13 Comments
… by people with traditional database background. Things are different with MySQL. There are many successful applications, using tens of thousands of… do run EXPLAIN for your queries, especially if you see them in slow query log. If you have trouble understanding EXPLAIN or optimizing…
Post: How does MySQL Replication really work?
January 9, 2013 By 9 Comments
… formats. These are covered pretty well in the MySQL manual here. Put simply, the events can be …sure it is SQL thread, then you want to understand what is the reason and that you can …that are limiting replication performance, not writes. Let me explain this further. Assume you have a RAID10 with …
