Post: High-load problems? Investigate them with 'pt-query-digest'
… is a little known goodie from Percona Toolkit for MySQL called pt-query-digest. One customer was suffering from periods of high… diagnostics information to review even if we couldn’t be logged in to...
View ArticlePost: More on MySQL transaction descriptors optimization
… the first post: single SELECT queries doing PRIMARY KEY lookups (aka QPS sysbench mode); same MySQL queries executed inside single-statement transactions (TPS… perfect case for read-only transaction...
View ArticlePost: Disconnecting a replication slave is easier with MySQL 5.5+ (RESET...
… log files. This looks great, but does it ensure the replica is disconnected from its master? Let’s try: mysql> stop slave; Query OK, 0 rows affected (0.00 sec) mysql> reset slave; Query OK, 0...
View ArticlePost: Experiences with the McAfee MySQL Audit Plugin
… user activity in MySQL has traditionally been challenging. Most data can be obtained from the slow or general log, but this involves…/audit.sock #audit_json_socket=1...
View ArticlePost: Is your MySQL buffer pool warm? Make it sweat!
…: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 thread-pool...
View ArticlePost: Rotating MySQL slow logs safely
… log that illustrates these best practices: /var/mysql/slow_query.log { nocompress create 660 mysql mysql size 1G dateext missingok notifempty sharedscripts postrotate /usr/local/bin/mysql -e ‘select...
View ArticleComment: pt-online-schema-change and binlog_format
… RBR can be an increase in Binary Log size depending on the types of queries you execute. It some well structured applications… one query). MySQL 5.6 also introduces binlog_row_image...
View ArticlePost: Changing an async slave of a PXC cluster to a new Master
….01 sec) node3 mysql> change master to master_host=’node2′, master_log_file=’node2.000002′, master_log_pos=2973899; Query OK, 0 rows affected (0.02 sec) node3 mysql> slave start; Query OK, 0...
View ArticlePost: Percona Server 5.1.69-14.7 now available: A drop in replacement for MySQL
… libdbd-mysql-perl package. Fixed by adding the package dependency. Bug fixed #1003776. XtraDB changed page tracking used to hold the log…_PAGES query started returning data to indicate an incomplete...
View ArticlePost: Percona Server 5.5.32-31.0 now available
… more elaborate analysis on the nature of the query to determine whether the query will cause uncertainty for replication or not. Bug… RPM installer script had the datadir hardcoded to /var/lib/mysql...
View ArticleComment: How to find MySQL queries worth optimizing ?
… ask for a rows with little more complicated query, it confuses me even more: mysql> explain select c from test_idx where… index Join type “range”, but I know that MySQL uses it for IN queries even...
View ArticleComment: How to Identify Bad Queries in MySQL
… ask for a rows with little more complicated query, it confuses me even more: mysql> explain select c from test_idx where… index Join type “range”, but I know that MySQL uses it for IN queries even...
View ArticlePost: High-load problems? Investigate them with 'pt-query-digest'
… is a little known goodie from Percona Toolkit for MySQL called pt-query-digest. One customer was suffering from periods of high… diagnostics information to review even if we couldn’t be logged in to...
View ArticlePost: Crash-resistant replication: How to avoid MySQL replication errors
…, This setting of 100000 total queries with 100 concurrent clients will run 100000/100 = 1000 queries per client 10 times in this…_update_relay_log on the slave. Set it to...
View ArticlePost: Percona Server for MySQL 5.5.31-30.3 now available
… could cause a memory leak if query cache was used together with InnoDB. Bug…log enabled and then restarted with the binary log disabled, Crash-Resistant Replication could overwrite the relay log info...
View ArticlePost: Another reason why SQL_SLAVE_SKIP_COUNTER is bad in MySQL
… a transaction on the master to break replication: master> BEGIN; Query OK, 0 rows affected (0.00 sec) master> DELETE FROM… HA_ERR_KEY_NOT_FOUND; the event’s master log mysql-bin.000002,...
View ArticleComment: What kind of queries are bad for MySQL?
…when it comes to MySQL. I personally focus on creating tools to help MySQL perform significantly better …bitmap indexes, flexviews for materialized views and shard-query for OLAP scale-out. Both...
View ArticlePost: Percona Server for MySQL 5.5.31-30.3 now available
… could cause a memory leak if query cache was used together with InnoDB. Bug…log enabled and then restarted with the binary log disabled, Crash-Resistant Replication could overwrite the relay log info...
View ArticlePost: Let's talk about Percona Server 5.6: Enterprise Grade MySQL (webinar)
… to MySQL 5.6, including a review of top deprecated features and their optimized replacements, enhancements to performance monitoring, slow query log, XtraDB… the most manageable, highest performance,...
View ArticlePost: Advanced MySQL Query Tuning: Webinar followup Q&A
… MySQL 5.1 +: Enable the slow query log with microsecond presision and log the query. To log all queries in the slow query log you can temporary set: long_query_time = 0 MySQL 5…The post Post:...
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