Scaling up a workload to many cores on a single host

Here are results for Shard-Query 2.0 Beta 1* on the Star Schema Benchmark at scale factor 10.  In the comparison below the “single threaded” response times for InnoDB are the response times reported in my previous test which did not use Shard-Query.

Shard-Query configuration

Shard-Query has been configured to use a single host.  The Shard-Query configuration repository is stored on the host.  Gearman is also running on the host, as are the Gearman workers.  In short, only one host is involved in the testing.

The …

I find myself flying to New York on Monday for some dealnews related business. Anytime I travel I try and find something fun to do at night. (Watching a movie by myself in Provo, Utah was kinda not that fun.) So, this week I asked on Twitter if anything was happening while I would be in town. Anything would do. A meetup of PHP/MySQL users or some design/css/js related stuff for example. Pretty much anything interesting. Well, later that day I received an IM from the brilliant John Allspaw, Senior VP of Technical Operations at Etsy. He wanted me to swing by the Etsy offices and say hi. Turns out it is only a block away from where I would be. Awesome! He also mentioned that he would like to have me come and speak at their offices some time. That would be neat too. I will have to plan better …

I have been writing a bit about Gearman lately, including installing it for PHP and Ubuntu, actually using it from PHP and also how I use persistent storage with Gearman. I'm moving on to look at adding jobs of different priorities.

I use Gearman entirely as a point to introduce asynchronous-ness in my application. There is a complicated and image-heavy PDF to generate and this happens on an automated schedule. To do this, I use the GearmanClient::doBackground method. This inserts a priority 1 job into my queue. …

I'm using gearman for the first time in a new project, and two things in particular were bothering me. Firstly, there doesn't seem to be a built-in way to see what's in the queue. Secondly, if the gearman server dies (which seemed quite likely when I was first getting to grips with this stuff and writing really buggy code!) you lose your queue. Therefore I decided that I would switch gearman over to running with persistent storage. My config file (this is Ubuntu 10.10) is in /etc/default/gearman-job-server and it contains the following snippet:

      # Use mysql as persistent queue store                                                                                                  
# PARAMS="-q libdrizzle --libdrizzle-host=10.0.0.1 --libdrizzle-user=gearman \                                                         
#                       --libdrizzle-password=secret --libdrizzle-db=some_db \ …

I wrote recently about having gearman in my application, however I have been seeing problems with the long-running PHP worker scripts. My logs had entries like this:

SQLSTATE[HY000]: General error: 2006 MySQL server has gone away

The worker is a Zend Framework application, run from the CLI, and it seemed like the Zend_Db_Adapter had no way of knowing when MySQL had let go of its end of the connection. I tried a few different things, including Zend_Db_Adapter::getConnection(), but without success - until I dug through the source code (with some help from a friend) and realised that ZF was not reconnecting at all if it thought it already had a connection. So instead, I expressly disconnected and reconnected the database handler. At bootstrap time, I place my database handle into the registry, so I simply added this at the start of the actual …

I use a MacBook Pro for my day-to-day operations here at CB1, INC. I’m a huge believer that a development environment should mimic the production environment, so I find myself running a couple virtual machines in VMware Fusion.

The following guide is a reference for myself as well as possibly a helpful resource for setting up your own Linux development environment. Here’s an checklist of the tasks to perform and software to install:

• Operating System
  • Ubuntu 10.10 64-bit: I use Ubuntu Desktop in dev and Ubuntu Server in production
  • Package updates and upgrades
  • Network configuration (at least 2 static IP addresses)
• Development Tools
  • C/C++ development environment
  • Autotools
  • Sun Java JDK
  …

The past two weeks have been both exciting and extremely busy, first traveling to Austin, TX for the first OpenStack Design Summit, and then back home to Portland, OR for The O’Reilly Open Source Conference (OSCON) and Community Leadership Summit. The events were great in different ways, and there was some overlap with OpenStack since we announced it on the first day of OSCON and created quite a bit of buzz around the conference. I want to comment on a few things that came up during these two weeks.

New Role

I’m now focusing on OpenStack related projects at Rackspace. I’m no longer working …

OpenSQLCamp is less than 4 months away, and I have finally gotten around to updating the site. Special thanks go to Bradley Kuzsmaul and the folks at Tokutek for getting the ball rolling and making the reservation at MIT. Using MIT means that we will have *free* reliable wireless guest access and projects.

OpenSQL Camp is a free unconference for people interested in open source databases (MySQL, SQLite, Postgres, Drizzle), including non-relational databases, database alternatives like NoSQL stores, and database tools such as Gearman. We are not focusing on any one project, and hope to see representatives from a variety of open source database projects attend. As usual I am one of the main organizers of Open SQL Camp (in previous years, Baron Schwartz, Selena Deckelmann and Eric Day have been main organizers too; this year Bradley Kuzsmaul is the other main organizer). The target audience …

Last week I was surprised to see this paper bubble back up on Planet MySQL. It describes the pros and cons of thread and event based programming for high concurrency applications (like a web server), arguing that thread-based programming is superior if you use an appropriate lightweight threading implementation. I don’t entirely disagree with this, but the problem is such a library does not exist that is standard, portable, and useful for all types of applications. We have POSIX threads in the portable Linux/Unix/BSD world, so we need to work with this. Other experimental libraries based on lightweight threads or “fibers” are really interesting as they can maintain your stack without all the normal overhead, but it is hard to get the scheduling correct for all …

I am back home from a good week at the 2010 O'Reilly MySQL Conference & Expo. I had a great time and got to see some old friends I had not seen in a while.

Oracle gave the opening keynote and it went pretty much like I thought it would. Oracle said they will keep MySQL alive. They talked about the new 5.5 release. It was pretty much the same keynote Sun gave last year. Time will tell what Oracle does with MySQL.

The expo hall was sparse. Really sparse. There were a fraction of the booths compared to the past. I don't know why the vendors did not come. Maybe because they don't want to compete with Oracle/Sun? In the past you would see HP or Intel have a booth at the conference. But, with Oracle/Sun owning MySQL, why even try. Or maybe they are not allowed? I don't know. It was just sad.

I did stop by the Maatkit booth and was embarrassed to tell …