January 30th, 2014


If you’re familiar with Japan, it should come as no surprise that Cassandra 日本 2014年 was well-organized and highly technical. As far as one-day conferences go, I found myself quite impressed by the high quality and technical nature of the talks.

After the commencement, Jonathan Ellis took the microphone to give his keynote. Since I’ve seen most of his material before, I chose to listen to the Japanese and was quite impressed at the abilities of the translators. Jonathan doesn’t gloss over technical information; he covered topics ranging from standard fare (for distributed systems people) such as transactions to Cassandra-specific topics like size-tiered compaction in level 0. The translators didn’t miss a beat. He covered features of Cassandra 2.0 and 2.1 from an engineering perspective. How they work, why they matter, and what to expect. His overview of changes to bloom filters was especially interesting.

Next up, Masahiro Kago of Spring8 talked about how Cassandra is being used along with Redis, ZeroMQ, and MessagePack to build a next-generation data logging system that can keep up with their growing needs. English-speaking readers can learn more about it here.

Following lunch, it was my turn to speak about designing for consistency. Because I couldn’t come up with a good title ahead of time, I called it “Tuning Consistency” but I don’t really like that title. Mostly what I talked about was how previous decades’ architectures are focused on the read-modify-write pattern and other patterns that make different tradeoffs to avoid it in favor of availability and partition tolerance.

The next talk was by Narita Takashi (@oranie), talking about the trials of managing a 100-node Cassandra cluster in production. Unfortunately, I had to step out about for a client meeting about halfway through his talk. What I saw was packed with useful information about how to manage Cassandra clusters. The slides are available. Even if you can’t read Japanese, I recommend paging through them as there is some English and many of the technologies he and his team use are easy to pick out.

I only got to catch the end of Aaron Morton’s talk. In the portion I saw, he was deep in the details of Cassandra, arming users with the knowledge they need to use and operate Cassandra in production.

The final talk I attended was Kazuhiro Yamato of Miracle Linux talking about an R&D project to scale Zabbix past the limits of RDBMS. The conclusion was clear: Cassandra can take more of a beating than its competitors. An interesting choice they made was to keep relational data in MySQL, allowing a port of only the high-throughput parts of the application to Cassandra while keeping the convenience of SQL for the fiddly bits.

At the conclusion of the sessions, a reception was held on the first floor. I got to learn a little more about what is going on with Cassandra in Japan and was not disappointed. Most users appreciate the strengths of our technology, so what I was really interested in is what I, as part of Datastax’s community team, can do to make the experience better for more users. The biggest problem I heard about was a lack of documentation in Japanese. Fair enough. I’ve looked about and what is available is often outdated or too shallow. Initiatives are already starting at Datastax to fix this for Japanese and other users outside of the world of English. Internationalization was also brought up, and is something I will be discussing with our product team next time I see them.

Jonathan and I also learned about many Cassandra installations we were not aware of – Cassandra is really starting to take off here, and that’s really exciting. Many of Japan’s best-known brands are already using Cassandra to drive mission-critical tasks and even more are in the development phase of building on Apache Cassandra.

All that said, the best part of the day for me was getting to know some of our users at a personal level. Everybody was excited about the possibilities of building always-on applications on top of Cassandra. When I started planning this trip, I was excited about the prospects of growing the community here in Japan, but had no idea where to start. I look forward to helping our new friends build the community!