Video and slides from the Google talk


I’m a little slow at posting this, because I’ve been really busy. Google had the video of the MythTV talk online a day after the talk, which was nice. I haven’t watched it myself, but hopefully it turned out ok. The talk got a little exciting when I had to reboot one of the machines mid talk because it wasn’t seated in its dock properly. Such is life I suppose.

Here are the slides for the talk. Hopefully they’ll help someone.


MythTV talk at Google


I’m giving a MythTV talk at Google in the next week (although I can’t find it on the events calendar at the moment, I’ll update this post when I do) so I’ve been playing with MythTV 0.21 a little more than I have in the past. Its pretty cool.

I’m still writing the talk, so I don’t know 100% what it will cover, but I’m thinking it would be good to include some of the stuff from 0.21 as a teaser. Storage groups, the flash player in MythWeb, and the tweaks to the theme system seem like good things to include. Does anyone have other things they think are really cool in 0.21?

Oh, and I’ll have to cover guide data for the US, so it might be time to catch up with my MythTV email backlog once again.

Hopefully in you live near Silicon Valley you can come along to the talk and we can chat afterwards.

Update: I found a Google blog post with the details. To quote the most important information:

Like all sessions of the Open Source Developers @ Google Speaker Series, Michael’s presentation will be open to the public. Doors open at 6:30 PM at our Mountain View campus; guests should plan to sign in at Building 43 reception upon arrival. Refreshments will be served and all are welcome and encouraged to attend. Michael’s presentation will also be taped and published along with all of the public Google Tech Talks.


A MythTV Jabber bot


While I love my wife and kids to distraction, the distraction bit is real. Then again, I’m sure they have a counter argument that I tend to end up deep in thought, and which point you could probably push me off my chair and I wouldn’t notice. Anyway, that’s mostly beside the point. What is relevant is for the first time in nearly a year (since 18 November 2005 to be exact, but who is counting?) I’m alone. All alone.

So, apart from watching the West Wing (which I haven’t seen before, and is fantastic), sleeping in, and going to a party tonight, I am coding.

What I’m writing is a follow on from my night hacking the other day, which was getting PyXMPP working with Google Talk. What I want is a bot which will take IM messages, and execute them using the MythTV front end. Oh, and it will display text using the on screen display if you ask nicely.

So, does anyone have any thoughts on if that sort of thing is useful to them? I think it sounds useful to me, but perhaps I’m odd.

Back to hacking.


MySQL Tech Talks


Three intrepid MySQLers came to Google after the user conference to give internal tech talks. They were kind enough to agree to us hosting them for other people to see. The first two are up, so I’ll mention those now, and put a link to the last one when it’s available…

Click on the thumbnail to be taken to the video.

Jay Pipes is a co-author of the recently published Pro MySQL (Apress, 2005), which covers all of the newest MySQL 5 features, as well as in-depth discussion and analysis of the MySQL server architecture, storage engines, transaction processing, benchmarking, and advanced SQL scenarios. You can also see his name on articles appearing in Linux Magazine and can read more articles about MySQL at his website. Jay Pipes is MySQL’s Community Relations Manager for North America.

Learn where to best focus your attention when tuning the performance of your applications and database servers, and how to effectively find the “low hanging fruit” on the tree of bottlenecks. It’s not rocket science, but with a bit of acquired skill and experience, and of course good habits, you too can do this magic!

Timour Katchaounov

The first part of this talk describes the main principles behind MySQL’s query optimiser and execution engine, how the optimiser transforms queries into executable query plans, what these plans look like, and how they are executed.

The second part of the talk describes the major improvements in the query engine of MySQL 5.0, and how these improvements can benefit the users of MySQL 5.0. The “greedy” optimiser reduces compilation time for big queries with orders of magnitude. The “index merge” access method provides a way to use more than one index for the same query. For faster plan execution and to allow better join orders, the 5.0 optimiser transforms most outer joins into inner joins.

The outer joins that cannot be transformed into inner ones are executed in a pipeline manner, so that no intermediate results need to be materialised. Finally, some GROUP BY and DISTINCT queries can be executed much faster thanks to “loose index scan” technique that reads only a fraction of an index.

The talk concludes with the near-future plans for new features coming in the next versions of MySQL.

Stewart Smith works for MySQL AB as a software engineer working on MySQL Cluster. He is an active member of the free and open source software community, especially in Australia. Although Australian, he does not dress like Steve Irwin—although if he wrestled crocodiles he probably would. He is a fan of great coffee, great beer, and is currently 39,000 feet above sea level.

part 1 – Introduction to MySQL Cluster The NDB storage engine (MySQL Cluster) is a high-availability storage engine for MySQL. It provides synchronous replication between storage nodes and many mysql servers having a consistent view of the database. In 4.1 and 5.0 it’s a main memory database, but in 5.1 non-indexed attributes can be stored on disk. NDB also provides a lot of determinism in system resource usage. I’ll talk a bit about that.

part 2 – new features in 5.1 including cluster to cluster replication, disk based data and a bunch of other things. anybody that is attending the mysql users conference may find this eerily familiar.

I can also talk about latest-and-totally-greatest developments and future stuff we’re working on. i can also take questions and constructive abuse 🙂

You can see a complete list of the MySQL tech talks at Google here.

Update: added Stewart’s talk now that it is online.


Twisted Python and Jabber SSL


Ok, so I thought it would be cool to be able to send Google Talk messages to my MythTV box. Can’t be too hard to write a twisted python jabber client can it? Well, after an hour of surfing, I give up. I have the simple jabber client example, but it totally doesn’t work with the Google servers, I suspect because it doesn’t do SSL. I can see one of the twisted.words maintainers filing bugs against the xish stuff too, which I suspect means it’s going to be a while.

A little bit disappointing me thinks.