September 17, 2014

Percona Server 5.6.13-61.0 first GA release is now available

Percona is glad to announce the first GA (Generally Available) release of Percona Server 5.6.13-61.0 on October 7th, 2013 (Downloads are available here and from the Percona Software Repositories. Based on MySQL 5.6.13, including all the bug fixes in it, Percona Server 5.6.13-61.0 is the first GA release in the Percona Server 5.6 series. All […]

Percona Server 5.6.11-60.3 first Release Candidate now available

Percona is glad to announce the first Release Candidate release of Percona Server 5.6.11-60.3 on June 3rd, 2013 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.6.11, including all the bug fixes in it, Percona Server 5.6.11-60.3 is the first RC release in the Percona Server 5.6 series. All of […]

SELECT UNION Results INTO OUTFILE

Here’s a quick tip I know some of us has overlooked at some point. When doing SELECT … UNION SELECT, where do you put the the INTO OUTFILE clause? On the first SELECT, on the last or somewhere else? The manual has the answer here, to quote: Only the last SELECT statement can use INTO […]

FlashCache: first experiments

I wrote about FlashCache there, and since that I run couple benchmarks, to see what performance benefits we can expect. For initial tries I took sysbench oltp tests ( read-only and read-write) and case when data fully fits into L2 cache. I made binaries for FlashCache for CentOS 5.4, kernel 2.6.18-164.15, you can download it […]

Why delayed flushing can result in less work

I can think of at least two major reasons why systems delay flushing changes to durable storage: 1. So they can do the work when it’s more convenient. 2. So they can do less work in total. Let’s look at how the second property can be true.

New SpecJAppServer results at MySQL and Sun.

As you likely have seen Sun has posted the new SpecJAppServer Results More information from Tom Daly can be found here These results are quite interesting for me as I worked on some of the previous SpecJAppServer Benchmarks several years ago while being employed by MySQL. These are great results, plus they can be relevant […]

MySQL Optimizer team comments on TPC-H Results

Yesterday I had a chance to speak to Igor – head of MySQL optimizer team and Timur – both of them expressed concern with TPC-H run results I posted and notes about little gains in MySQL 6.0. Do not get this post wrong. I’m not saying MySQL 6.0 SubQuery optimizations are non existent or priorities […]

Speeding up GROUP BY if you want aproximate results

Doing performance analyzes today I wanted to count how many hits come to the pages which get more than couple of visits per day. We had SQL logs in the database so It was pretty simple query:

Unfortunately this query ran for over half an hour badly overloaded server and I had to kill […]

MySQL and PostgreSQL SpecJAppServer benchmark results

Listening to Josh Berkus presentation on OSCON today I decided to take a closer look at SpecJAppServer benchmarks results which were published by PostgreSQL recently and which as Josh Puts it “This publication shows that a properly tuned PostgreSQL is not only as fast or faster than MySQL, but almost as fast as Oracle (since […]

PHP Large result sets and summary tables.

We’re working with web site preparing for massive growth. To make sure it handles large data sets as part of the process we work on generation test database of significant size as testing your application on table with 1000 rows may well give you very dangerous false sense of security. One of the process web […]