November 24, 2014

More Gotchas with MySQL 5.0

Working on large upgrade of MySQL 4.1 running Innodb to MySQL 5.0 and doing oprofile analyzes we found very interesting issue of buf_get_latched_pages_number being responsible for most CPU usage. It did not look right. The close look revealed this is the function which is used to compute number of latched pages in Innodb Buffer Pool, […]

InnoDB vs MyISAM vs Falcon benchmarks – part 1

Several days ago MySQL AB made new storage engine Falcon available for wide auditory. We cannot miss this event and executed several benchmarks to see how Falcon performs in comparison to InnoDB and MyISAM. The second goal of benchmark was a popular myth that MyISAM is faster than InnoDB in reads, as InnoDB is transactional, […]

Introducing new type of benchmark

Traditionally the most benchmarks are focusing on throughput. We all get used to that, and in fact in our benchmarks, sysbench and tpcc-mysql, the final result is also represents the throughput (transactions per second in sysbench; NewOrder transactions Per Minute in tpcc-mysql). However, like Mark Callaghan mentioned in comments, response time is way more important […]

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 […]

Beware the Innodb Table Monitor

As I stated in my last post, I decided to use the Innodb Table monitor to diagnose an Index count mismatch error a customers found in their mysqld.err log to verify if the problem still existed. The Innodb Table Monitor has existed for basically forever in Innodb (the MySQL manual discusses it back in the 4.1 […]

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 […]

Using Flexviews – part two, change data capture

In my previous post I introduced materialized view concepts. This post begins with an introduction to change data capture technology and describes some of the ways in which it can be leveraged for your benefit. This is followed by a description of FlexCDC, the change data capture tool included with Flexviews. It continues with an […]

Estimating Replication Capacity

It is easy for MySQL replication to become bottleneck when Master server is not seriously loaded and the more cores and hard drives the get the larger the difference becomes, as long as replication remains single thread process. At the same time it is a lot easier to optimize your system when your replication runs […]

PBXT in tpcc-like benchmark

Finally I was able to run PBXT 1.0.11 pre-GA in tpcc-like workload, apparently there was bug with did not allow me to get the result earlier, and I am happy to see that PBXT team managed it. For initial runs I took tpcc 100 warehouses ( about 10GB of data) which fully fits into memory […]

XtraDB feature: save / restore buffer pool

We recently released XtraDB-9, and while we did not highlight it in announcement, the release-making feature is ability to save and restore InnoDB buffer pool. The idea is not new and was originally developed by Jeremy Cole (sorry, I do not have the link on hands) some time ago, and now we implemented it in […]