… release of version 2.1 of Percona Toolkit. Percona Toolkit is the essential suite of administrative tools for MySQL. With this release…. However, it had many limitations and missing features. The new 2.1 version of the tool removes those limitations and makes the tool… a hot topic at the upcoming MySQL Conference and there will be many talks about various parts of the toolkit: A 3…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
…enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’…index lookups have some limitations in cases such as range scans, where index parts after the part on which range …condition defined as: l_partkey = x and l_quantity >= 1 and l_quantity = 1 and l_…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
…_name, c_address, c_comment order by revenue desc LIMIT 20; In-memory workload Now let’s see …_tmp_disk_tables 1 1 1 1 1 Created_tmp_tables 1 1 1 1 1 Handler_mrr_init N/A 0 0 1 1 Handler_mrr_rowid_…MySQL 5.6/MariaDB 5.5 This is another area of improvement in the optimizer, as it is clearly a part…
Post: Announcing Percona XtraBackup 2.0.0 GA
April 4, 2012 By 11 Comments
…release contains no changes from the last beta (1.9.2), only the version number has changed…. utilities, which also had a number of other limitations (e.g. could not be used with parallel… Percona XtraBackup will be part of the topics at the upcoming Percona Live MySQL Conference and Expo (register …
Post: MySQL Limitations Part 4: One thread per connection
October 27, 2010 By 14 Comments
… on what’s seriously limiting MySQL in core use cases (links: part 1, 2, 3). This post is about the way MySQL handles connections, allocating one thread per connection to the server. MySQL is… them. That’s why I listed those as major limitations. And because MySQL is a multi-threaded database for Web usage that…
Post: MySQL Limitations Part 3: Subqueries
October 25, 2010 By 20 Comments
… third in a series on what’s seriously limiting MySQL in certain circumstances (links: part 1, 2). This post is about subqueries, which in…, followed by N queries to table b. This is because MySQL rewrites the query to make the inner query dependent on…. And many MySQL users have learned to simply write JOINs instead, so it isn’t that much of a limitation. But it…
Post: MySQL Limitations Part 2: The Binary Log
October 23, 2010 By 11 Comments
… in a series on what’s seriously limiting MySQL in certain circumstances (links: part 1). In the first part, I wrote about single-threaded replication… data in the server. The binary log is a real limitation in MySQL. The binary log is necessary not only for replication… transaction logs, so there’s even precedent for this among MySQL storage engines. And there is Galera’s multi-master synchronization…
Post: MySQL Limitations Part 1: Single-Threaded Replication
October 20, 2010 By 16 Comments
…” limitations Postgres has overcome for specific use cases. I decided to write a series of blog posts on MySQL‘s unsolved severe limitations. I mean limitations that really hobble it for major, important… solutions represent different types of trade-offs. For example, solution 1) only works for specific uses, and I don’t think…
Post: MySQL on Amazon RDS part 1: insert performance
March 15, 2011 By 37 Comments
… Service (RDS) is a cloud-hosted MySQL solution. I’ve had some clients hitting performance limitations on standard EC2 servers with EBS…
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 12 Comments
… it parses by running the SELECT portion, adding LIMIT 0 to the SELECT part of the query. convert.php This script takes… the MV. mysql> select mview$pk as rank, customer_id, total_price, total_lines from demo.dashboard_top_customers limit 10; +——+————-+————-+————-+ | rank… some line items from orders: mysql> delete -> from order_lines -> where order_id -> between 1 and 100 -> limit 500; Query OK, 484 rows…
