MySQL Replication and Slow Queries
I just filed a bug regarding slow queries executed by replication thread are not being logged to the slow query log.This is not a big deal but it is ugly little gotcha which I think few people know...
View ArticleMySQL Slow query log in the table
As of MySQL 5.1 get MySQL slow query log logged in mysql.slow_log table instead of the file as you had in previous versions. We rarely would use this feature as it is incompatible with our slow query...
View ArticleMySQL 4 to MySQL 5 Upgrade performance regressions
This week I already had two serious performance regression cases when upgrading from MySQL 4.0 and 4.1 to MySQL 5.0. By serious I mean several times performance difference not just 5-10% you often see...
View ArticleHow to load large files safely into InnoDB with LOAD DATA INFILE
Recently I had a customer ask me about loading two huge files into InnoDB with LOAD DATA INFILE. The goal was to load this data on many servers without putting it into the binary log. While this is...
View ArticleIdentifying the load with the help of pt-query-digest and Percona Server
OverviewProfiling, analyzing and then fixing queries is likely the most oft-repeated part of a job of a DBA and one that keeps evolving, as new features are added to the application new queries pop up...
View ArticleImplications of Metadata Locking Changes in MySQL 5.5
While most of the talk recently has mostly been around the new changes in MySQL 5.6 (and that is understandable), I have had lately some very interesting cases to deal with, with respect to the...
View ArticlePERFORMANCE_SCHEMA vs Slow Query Log
A couple of weeks ago, shortly after Vadim wrote about Percona Cloud Tools and using Slow Query Log to capture the data, Mark Leith asked why don’t we just use Performance Schema instead? This is an...
View ArticleHow to identify and cure MySQL replication slave lag
Here on the Percona MySQL Support team, we often see issues where a customer is complaining about replication delays – and many times the problem ends up being tied to MySQL replication slave lag. This...
View ArticlePercona Server 5.5.41-37.0 is now available
Percona is glad to announce the release of Percona Server 5.5.41-37.0 on January 9, 2015. Based on MySQL 5.5.41, including all the bug fixes in it, Percona Server 5.5.41-37.0 is now the current stable...
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