… Query Cache performs query lookup in the cache before query parsing, so if result is served from query cache, query parsing step is saved. Queries…query cache. Now lets speak a bit about Query Cache configuration and mainance. MySQL Manual is pretty good on this: Query Cache Query Cache Status Query…
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 20 Comments
… view, making it available for querying: mysql> call flexviews.enable( -> flexviews.get_id(‘demo’,'dashboard_customer_sales’)); Query OK, 0 rows affected (41… monthly summary. The monthly summary is actually another MV. This saves a significant amount of time. If this MV did not… in descending order: mysql> call flexviews.create( -> ‘demo’,'dashboard_top_customers’,'COMPLETE’); Query OK, 1 row affected (0.00 sec) mysql> call flexviews…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…order’; /*!40101 SET character_set_client = @saved_cs_client */; CREATE TABLE `dim_flight` ( `…from 1988 to 2010′; mysql> use ontime1; Database changed mysql> show table status like ‘ontime…from the ./run_query command, called pivot_results cd shard-query/ $ ./run_query < queries.sql | tee raw |./…
Post: MySQL 5.6.10 Optimizer Limitations: Index Condition Pushdown
March 14, 2013 By 2 Comments
… of the MySQL 5.6.10 optimizer. Other interesting things to notice: ICP is a great new feature that already saved us… enough. Do you want to know more about the MySQL 5.6 query optimization improvements in a practical way, with real-life…-party, independent and technical opinion about the new features of MySQL query planner? Are you not yet familiar with terms like MRR…
Post: MySQL Indexing Best Practices: Webinar Questions Followup
August 16, 2012 By 4 Comments
…to be on that column. That would clearly save indexing space. Is this a reasonable performance optimization….both directions for different queries. This will use fast primary key for some queries and use key …fragmented. I also would note there are some MySQL optimizer restrictions in how well it can …
Post: Reasons for MySQL Replication Lag
July 29, 2011 By 9 Comments
… as increasing buffer pool size could cause performance problems. MySQL Restart MySQL Restarts may include recovery time but what is the most… 24+hours to feel 200GB buffer pool. Automatic Buffer Pool Save/Restore available in Percona Server is great help in this… be even system which queries mysql. I’ve seen monitoring updates which would add excessively expensive and frequent query on information_schema which…
Post: Why MySQL could be slow with large tables ?
June 9, 2006 By 141 Comments
… keys in Innodb which combine index access with data access, saving you IO for completely disk bound workloads. There are certain…. In MySQL single query runs as single thread (with exeption of MySQL Cluster) and MySQL issues IO requests one by one for query execution, which means if single query execution time is…
Post: Review of MySQL 5.6 Defaults Changes
October 8, 2012 By 10 Comments
… posted the great summary of defaults changes in MySQL 5.6 compared to MySQL 5.5 In general there are a lot… also little “savings” in keeping this value low – 64K or even more would be good default. query_cache_size = 1M Query cache remains…-factoring to be able to deal with simple and complicated queries efficiently automatically. join_buffer_size = 256k The default is now…
Post: Percona Live MySQL Conference and Expo 2013 – News from the Committee – Tutorial Selection Complete
December 3, 2012 By 1 Comment
… register NOW for this conference, and the Super Saving Registration deadline ends on December 28th, so … schema design and writes a lot of queries. High Availability Tutorials One of the clearly …was not the case at a MySQL conference. There are several MySQL HA related tutorials: Using Tungsten …
Post: Is there room for more MySQL IO Optimization?
January 3, 2013 By 11 Comments
… no overhead of double buffering and I can save the limited amount of file system cache I… files, binary log, FRM files, MySQL MyISAM system tables etc. Starting MySQL 5.5 MySQL uses asynchronous IO which should… to large full table scan and index scan queries, though this is really not the point. The…
