September 19, 2014

MySQL EXPLAIN limits and errors.

Running EXPLAIN for problematic queries is very powerful tool for MySQL Performance optimization. If you’ve been using this tool a lot you probably noticed it is not always provide adequate information. Here is list of things you may wish to watch out. EXPLAIN can be wrong – this does not happen very often but it […]

Measuring the amount of writes in InnoDB redo logs

Choosing a good InnoDB log file size is key to InnoDB write performance. This can be done by measuring the amount of writes in the redo logs. You can find a detailed explanation in this post. To sum up, here are the main points: The redo logs should be large enough to store at most […]

A case for MariaDB’s Hash Joins

MariaDB 5.3/5.5 has introduced a new join type “Hash Joins” which is an implementation of a Classic Block-based Hash Join Algorithm. In this post we will see what the Hash Join is, how it works and for what types of queries would it be the right choice. I will show the results of executing benchmarks […]

Identifying the load with the help of pt-query-digest and Percona Server

Overview Profiling, 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 that need to be analyzed and fixed. And there are not too many tools out there that can make […]

The two even more fundamental performance metrics

In a recent blog post, I wrote about four fundamental metrics for system performance analysis. These are throughput, residence time, “weighted time” (the sum of all residence times in the observation period — the terminology is mine for lack of a better name), and concurrency. I derived all of these metrics from two “even more […]

Is VoltDB really as scalable as they claim?

Before I begin, a disclaimer. VoltDB is not a customer, and did not pay Percona or me to investigate VoltDB’s scalability or publish this blog post. More disclaimers at the end. Short version: VoltDB is very scalable; it should scale to 120 partitions, 39 servers, and 1.6 million complex transactions per second at over 300 […]

Percona is hiring performance experts

Percona is hiring. We’ve added several experts recently and we’re growing at a fast but sustainable pace. The demand for our services is strong, and we have openings for more experts in the next couple of months. Let me explain a little about what we’re looking for at the moment. While we do have a […]

Site was down today, support and web hosting.

During last one and a half year we had pretty good track record with MySQL Performance Blog – there were times when site was slow (especially when backup was running) but I do not remember significant downtime, until today we went down for few hours. All this time the site was running on dedicated server […]

Commodity Hardware, Commodity Software and Commodity People

In the previous post I mentioned not all architectures and solutions work for Commodity People, and people seems to agree with me. Number of vendors would claim they are in Commodity Software or Hardware business but few would probably mention they are doing it for Commodity People, because few people would like to be called […]