The latest from the MySQL community

Checkpointing — which involves periodically writing out dirty pages from memory — is central to the design of crash recovery for both TokuDB and InnoDB. A key issue in designing a checkpointing system is how often to checkpoint, and TokuDB takes a very different approach from InnoDB. How often and how much InnoDB checkpoints is complicated, but under certain workloads it can be relatively infrequent. In contrast, TokuDB runs a complete checkpoint starting one minute after the last one ended.

Frequent checkpoints make for fast recovery. Once MySQL crashes, the storage engine needs to replay the log to get back to a correct state. The length of the log is a function of the time since the last checkpoint for TokuDB and a more complicated function of the workload for InnoDB. And replaying the log is single threaded. So TokuDB recovers in minutes, and …

A key feature of our new TokuDB v6.0 release, which I have been blogging about this week, is compression. Compression is always on in TokuDB, and the compression we’ve achieved in the past has been quite good. See a previous post on the 18x compression achieved by TokuDB v5.0 on one benchmark. In our latest release, we’ve updated the way compression works and got 50% improvement on compression.

I decided to present numbers on the same set of data as the old post, so see that post for experimental details.

But first, what are the changes? TokuDB compresses large blocks of data — on the order of MB, rather than the 16KB that InnoDB uses — …

We are excited to announce TokuDB® v6.0, the latest version of Tokutek’s flagship storage engine for MySQL and MariaDB.

This version offers feature and performance enhancements over previous releases, support for XA (two-phase transactional commits), better compression, and reduced performance variability associated with checkpointing. This release also brings TokuDB support up to date on MySQL v5.1, MySQL v5.5 and MariaDB v5.2. There’s a lot of great technical stuff under the hood in this release and I’ll be reviewing the improvements one-by-one over the course of this week.

I’ll be posting more details about the new features and performance, so here’s an overview of what’s in store.

Replication Slave Lag

One of the things TokuDB does well is single-threaded insertions, which translates directly into less slave lag. With TokuDB v6.0, we introduce support for XA, which insures for …

After 15 years of slide show technology, I thought that we need to change the way we do presentations. And since I am advocating radical changes, I will eat my own dog food and be the first to present a MySQL session using 3D technology.

Since watching Avatar a few years ago, I thought that using this technology would make my presentations truly amazing. However, two years ago a 3d projector was prohibitively expensive. Now, instead, it is affordable, and fits in my briefcase!

What I needed, though, was a compelling reason for using 3d vs. traditional presentations. And I found it. As I have mentioned recently, I am working with the coolest replication technology on earth. Explaining this technology is often challenging. While regular replication …

MySQL version 4.1 was quite revolutionary. The main reason for that was support for sub-queries.1

However since then MySQL users were rather discouraged to use that functionality, basically due to the implementation’s poor performance  and forced to build complicated queries based on joins rather than on subqueries.

Of course you can do some effort to optimize your subquery with sometimes very good results2. Not always it’s easy or even possible if you can’t change the code though.

You’d say it’s not a problem for typical OLTP, web based traffic at all, just don’t use subqueries! That’s true, …

The second week of April will be quite a busy one

Tuesday, April 10

April 10th is Tutorial day at the Percona Live MySQL Conference and Expo.

On that day, I will present a classic: MySQL Replication 101. This is a topic traditionally presented by a MySQL engineer. However, since Oracle seems not to be eager to send anyone to the conference, I volunteered to the task, and I have let everyone know that, if Oracle change its mind and sends some engineers at the conference, I will happily have one of my former colleagues from the replication team as co-speaker.

Wednesday, April 11

The conference will be in full swing when the regular sessions (and the keynotes!) start. From my side, it is noteworthy the talk about …

I for one can say that I’m truly excited that MariaDB will be part of Percona Live Santa Clara. The MariaDB session list includes:

• A tutorial: Improving MySQL/MariaDB query performance through optimizer tuning by Timour Katchaounov and Sergey Petrunia. You can benefit from this even as a stock MySQL user naturally.
• MySQL Plugins – why should I bother? by Sergei Golubchik is again something that isn’t only MariaDB specific since MySQL also has a plugin architecture. I don’t know if Sergei will talk about authentication plugins as …

Several months ago I suggested having lightning talks at Percona Live MySQL Conference and Expo 2012, and I also offered to help.

Then I forgot about that for a while, until I saw the announcement that there was a call for Lightning Talks. Great! I submitted two proposals, and asked my colleagues to do the same, and also encouraged many good speakers I know to submit something.

The deadline for lightning talks submission passed, and I was told that my offer to help had been accepted, and I was in charge of lightning talks! OK. I would have preferred being told before the CfP, but an offer to help is an offer to help, and thus I went through the motions of evaluating the talks, sending notices to the winners, consoling the losers, and giving hope to the few brave ones who will replace the winners if they don't show up.

The talks that you will …

Oh boy, I'm starting to feel the stress of having to prepare a little bit of this and a little bit of that for the upcoming MySQL User Conference (Santa Clara, April 10 to 13). But I wanted to also jump on this meme and list a few sessions I definitively want to attend:

I'm speaking, so I suppose I need to attend:

• How to evaluate which MySQL High Availability solution best suits you. This 3 hour tutorial I'm co-presenting with Ben Mildren, a former Nokia collague who now works with Pythian.

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Tokutek and Percona are giving away free tickets to the Percona Live MySQL Conference and Expo (worth $995 each), and you can win them! We’re also giving away copies of High Performance MySQL, 3rd Edition (worth $55 each).

This year’s event is the best ever, with a better lineup of talks and speakers than ever before.  It’s the one event you should not miss if you’re at all interested in MySQL.  We really want you to be there — and that’s why we’re joining with Percona to give away free tickets! It’s easy to enter:

• Follow our Twitter feed, and retweet us when we mention this contest
• Tweet “My favorite #MySQL conference …