…not complain. If we execute the same sentences in MySQL 5.6, the second ALTER will also succeed -and the index …ADD INDEX (col2); Query OK, 0 rows affected, 1 warning (0.56 sec) Records: 0 Duplicates: 0 Warnings: 1 mysql> SHOW WARNINGS\G *************************** 1. row *************************** …
Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency
May 22, 2013 By Leave a Comment
…query is tested again without restarting the database. The first test is described as the cold test, and the second… #2 Flight #2 is similar to Flight #1. MyISAM is faster than InnoDB when the…=/mnt/mysql56/data basedir=/usr/local/mysql socket=/var/lib/mysql/mysql.sock user=justin innodb_buffer_pool…
Post: Is your MySQL buffer pool warm? Make it sweat!
April 16, 2013 By 6 Comments
…3307/slow | percona-playback –mysql-host 127.0.0.1 –mysql-username playback –mysql-password PaSSwOrd –mysql-schema schema_name –query-log-stdin –dispatcher-plugin … each containing roughly 1M queries. We warmed the cold database with the first chunk and replayed the second chunk after the …
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
… the first post: single SELECT queries doing PRIMARY KEY lookups (aka QPS sysbench mode); same MySQL queries executed inside single-statement transactions (TPS… on case #1. Which is the perfect case for read-only transaction optimization in MySQL 5.6, because all SELECT queries in the… cores/32 cpu threads) All are NUMA boxes, but the second one has a higher QPI bandwidth, and the third one…
Post: MySQL and Percona Server in LinkBench benchmark
May 8, 2013 By 18 Comments
…second for MySQL 5.6.11. Conclusion: In CPU-bounds case MySQL performs quite well, though we can see small performance drop in MySQL…5000 table-definition-cache=1000 query_cache_size=0 query_cache_type=0 performance_…partitions=8 innodb_buffer_pool_instances=1 innodb_adaptive_flushing_method=keep_…
Post: Why MySQL Performance at Low Concurrency is Important
March 27, 2013 By 8 Comments
… of 1 serves as an important baseline that offers the best response times (MySQL server does not use multiple threads to execute query… and how the system scales with increasing concurrency in effect. Second, there are many cases in which single-thread execution is… concurrency of 1 and the same tool is not possible. Want to talk more about performance? Come to Percona Live MySQL Conference…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
… version of MySQL used was Percona Server 5.5.30-rel30.1-465. Each test was allowed to run for 7200 seconds, and the first 3600 seconds were discarded as… join_buffer_size = 4M thread_cache_size = 1000 query_cache_size = 0 query_cache_type = 0 ft_min_word_len = 4 thread…
Comment: State of the art: Galera - synchronous replication for InnoDB
April 23, 2013 By 15 Comments
… i/o on it that I have seen when running mysql 5.1 or mariadb 5.5 on the same hardware in… able to write 100,000 queries in about 50-60 seconds to mysql 5.1 and in about 6-9 seconds on mariadb 5.5…-queries=100000 MariaDB-Galera-server-5.5.29-1.x86_64 mysql-5.1.67-1.el6_3.x86_64 MariaDB-server-5.5.30-1…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
… points you need to attack the right query in the right way. But vanilla MySQL does have its limitations, it reports only… of long_query_time=0, because if you set it to some other value say 0.1 seconds, it will miss all queries shorter… the queries that you can use to gather more data about the underlying tables involved and the query execution plan used by MySQL…
Post: MySQL 5.6.10 Optimizer Limitations: Index Condition Pushdown
March 14, 2013 By 2 Comments
… was the following query in particular that had this surprising outcome: mysql> SELECT * FROM cast_info WHERE role_id = 1 and note like… from the “rows” value seen above. This is because the second part of the condition -note like ‘%Jaime%’- is actually tested…-party, independent and technical opinion about the new features of MySQL query planner? Are you not yet familiar with terms like MRR…
