October 25, 2014

Why do you need many apache children ?

I already wrote kind of about same topic a while ago and now interesting real life case makes me to write again Most Web applications we’re working with have single tier web architecture, meaning there is just single set of apache servers server requests and nothing else – no dedicated server for static content, no […]

Implementing SchemaSpy in your MySQL environment

Lately I have been working with a set of customers on a longer term basis which has given me time to explore new tools using their environments.  One tool that I am finding very helpful is called SchemaSpy. SchemaSpy is a Java-based tool (requires Java 5 or higher) that analyzes the metadata of a schema in […]

Why do we care about MySQL Performance at High Concurrency?

In many MySQL Benchmarks we can see performance compared with rather high level of concurrency. In some cases reaching 4,000 or more concurrent threads which hammer databases as quickly as possible resulting in hundreds or even thousands concurrently active queries. The question is how common is it in production ? The typical metrics to use […]

Percona Live MySQL Conference and Expo 2013 – News from the Committee – Part 1

I was honored to be asked to be a member of the committee for the “big” MySQL conference: Percona Live MySQL Conference and Expo 2013 in Santa Clara, CA.  Personally, I’ve been attending this conference for 6 or 7 years and missing it only when my wife was pregnant with a due date in April […]

Hijacking Innodb Foreign Keys

I guess I’m first to post in 2012 so Happy New Year all blog readers ! Now back to HardCore MySQL business – foreign Keys. MySQL supported Foreign Keys for Innodb for many years, yet rudimentary support initially added in MySQL 3.23.44 have not been improved in new releases as much as I’d like. We […]

How Innodb Contention may manifest itself

Even though multiple fixes have been implemented in Percona Server and MySQL 5.5, there are still workloads in which case mutex (or rw-lock) contention is a performance limiting factor, helped by ever growing number of cores available in the systems. It is interesting though the contention may manifest itself in the different form from the […]

Tom Basil (formerly MySQL’s Director of Support) Joins Percona

Percona has a new Chief Operating Officer! It is Tom Basil, who was Employee #11 at MySQL and led the Support organization there for almost eight years. He was the founding Director of Support at MySQL, and built it into a team of about 60 people all across the world. Tom was legendary as a […]

Resyncing table on MySQL Slave

Sometimes MySQL Replication may run out of sync – because of its own buts or operational limitations or because of application mistake, such as writing to the slave when you should be only writing to the master. In any case you need slave to be synced with Master. To discover the difference between Master and […]

How simple answer are you looking for ?

I’ve got an interesting comment the other day saying “I’ve heard Jay Pipes saying indexes with cardinality lower than 30% are worthless, true?” That is interesting question and it has different answers depending on who is asking. A lot of people want to hear simple answers to the questions because they would be overwhelmed by […]

Content delivery system design mistakes

This week I helped dealing with performance problems (part MySQL related and part related to LAMP in general) of system which does quite a bit of content delivery, serving file downloads and images – something a lot of web sites need to do these days. There were quite a bit of mistakes in design for […]