Search Results for: too many open files

MySQL server memory usage troubleshooting tips

There are many blog posts already written on topics related to “MySQL server memory usage,” but nevertheless there are some who still get confused when troubleshooting issues associated with memory usage for MySQL. As a Percona support engineer, I’m seeing many issues regularly related to heavy server loads – OR OOM killer got invoked and […]

Analyzing WordPress MySQL queries with Query Analytics

This blog, MySQLPerformanceBlog.com, is powered by WordPress, but we never really looked into what kind of queries to MySQL are used by WordPress. So for couple months we ran a Query Analytics (part of Percona Cloud Tools) agent there, and now it is interesting to take a look on queries. Query Analytics uses reports produced […]

QA: Advanced Option Combinatorics (Pairwise Testing): Combinatorial mysqld Option Test Case Generation

How do we ensure that, when we have 35+ testable option combinations for mysqld, we test each and every combination of them? For example: will a different innodb_log_file_size combined with more innodb_log_files_in_group and a modified innodb_fast_shutdown setting truly not affect Percona’s log archiving feature? Most option-related bugs are caused by the setting of 1 or […]

InnoDB performance optimization basics (redux)

I recently stumbled upon a post that Peter Zaitsev published back in 2007 titled “Innodb Performance Optimization Basics.” It’s a great post and reading it inspired me to examine what’s changed in the nearly six years that have followed in terms of MySQL, Percona Server – as well as in all of the other now-available […]

InnoDB Full-text Search in MySQL 5.6: Part 3, Performance

This is part 3 of a 3 part series covering the new InnoDB full-text search features in MySQL 5.6. To catch up on the previous parts, see part 1 or part 2 Some of you may recall a few months ago that I promised a third part in my InnoDB full-text search (FTS) series, in […]

Checking B+tree leaf nodes list consistency in InnoDB

If we have InnoDB pages there are two ways to learn how many records they contain: PAGE_N_RECS field in the page header Count records while walking over the list of records from infimum to supremum In some previous revision of the recovery tool a short summary was added to a dump which is produced by […]

MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark

So far most of the benchmarks posted about MySQL 5.6 use the sysbench OLTP workload.  I wanted to test a set of queries which, unlike sysbench, utilize joins.  I also wanted an easily reproducible set of data which is more rich than the simple sysbench table.  The Star Schema Benchmark (SSB) seems ideal for this. […]

MySQL 5.5 and MySQL 5.6 default variable values differences

As the part of analyzing surprising MySQL 5.5 vs MySQL 5.6 performance results I’ve been looking at changes to default variable values. To do that I’ve loaded the values from MySQL 5.5.30 and MySQL 5.6.10 to the different tables and ran the query:

Lets go over to see what are the most important changes […]

Announcing Percona Server 5.1.66-14.2

Percona is glad to announce the release of Percona Server 5.1.66-14.2 on January 15th, 2013 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.1.66, including all the bug fixes in it, Percona Server 5.1.66-14.2 is now the current stable release in the 5.1 series. All of Percona‘s software is open-source and free, all the details of the release can […]