April 19, 2014

Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact

I have been working with Peter in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking optimizer enhancements one by one. So in the same way this blog post is aimed at a new optimizer enhancement Index Condition Pushdown (ICP). Its available […]

Percona Server vs MySQL on Intel 320 SSD

If you are terrified by the stability of the results in MySQL in my previous post, I am going to show what we can get with Percona Server. This is also to address the results presented there Benchmarking MariaDB-5.3.4

Benchmarking Galera replication overhead

When I mention Galera replication as in my previous post on this topic, the most popular question is how does it affect performance. Of course you may expect performance overhead, as in case with Galera replication we add some network roundtrip and certification process. How big is it ? In this post I am trying […]

Performance problem with Innodb and DROP TABLE

I’ve been working with an application which does a lot of CREATE and DROP table for Innodb tables and we’ve discovered DROP TABLE can take a lot of time and when it happens a lot of other threads stall in “Opening Tables” State. Also contrary to my initial suspect benchmarking create/drop table was CPU bound […]

Sample datasets for benchmarking and testing

Sometimes you just need some data to test and stress things. But randomly generated data is awful — it doesn’t have realistic distributions, and it isn’t easy to understand whether your results are meaningful and correct. Real or quasi-real data is best. Whether you’re looking for a couple of megabytes or many terabytes, the following […]

Impact of the number of idle connections in MySQL

Be careful with my findings, I appear to have compile in debug mode, I am redoing the benchmarks. Updated version here. I recently had to work with many customers having large number of connections opened in MySQL and although I told them this was not optimal, I had no solid arguments to present. More than […]

Sharing an auto_increment value across multiple MySQL tables (revisited)

A couple of weeks ago I blogged about Sharing an auto_increment value across multiple MySQL tables. In the comments, a few people wrote in to suggest alternative ways of implementing this.  I just got around to benchmarking those alternatives today across two large EC2 machines:

MySQL-Memcached or NOSQL Tokyo Tyrant – part 3

This is part 3 of our series.  In part 1 we talked about boosting performance with memcached on top of MySQL, in Part 2 we talked about running 100% outside the data with memcached, and now in Part 3 we are going to look at a possible solution to free you from the database.  The […]

Query Profiling with MySQL: Bypassing caches

Quite frequently I run into question like this “I’m using SQL_NO_CACHE but my query is still much faster second time I run it, why is that ? The answer to this question is simple – because SQL_NO_CACHE only bypasses query cache but it has no change on other caches, which are MySQL Caches – Innodb […]

Looking for High Performance MySQL Interns

We have yet another opening at MySQL Performance Blog. We’re looking for Intern position (with limited compensation) to work on project of MySQL Performance research and analysis, developing and running benchmarks under our guidance, writing WhitePapers and articles. We feel this would be perfect part time position for the Computer Science student interested in High […]