Hi Hyunsik, Thank you very much for sharing the roadmap. I am very excited for the 0.8.0 release and for the projects on the roadmap for future releases.
I agree with Min that Tajo on YARN will be an important project. I think there will be a good amount of work to not only have Tajo run on YARN but also run well on a YARN cluster co-resident with other YARN applications. I think through this effort, we will likely also find areas of for improving multi-tenancy in YARN as well since YARN is still relatively young and has not been battle-tested that much yet. As you mentioned, one of the projects I would like to focus on is adding support for nested schemas and non-scalar types. This way, we would be able to take full advantage of columnar storage formats like Parquet, which is designed to work well with nested schemas. I understand that this will be a significant project, but I think it may be possible to divide up the work as I have done with the sub-tasks to TAJO-710 and push out support for each type incrementally across different releases. Another area that I would like to learn some more about is partitioning. I have just begun to look at TAJO-283 and am still ramping up on some of the context and the current status of the effort, but I am interested in exploring the possibility of enabling smart dynamic partitioning based on the way a table is queried but avoiding some of the current problems of dynamic partitioning such as creating too many files. One possible approach that I am thinking about is the possibility of building indices that point to offsets within files. Anyway, this is still more of a research problem, but is one that I would like to explore. Thanks, David On Apr 3, 2014, at 10:24 PM, Hyunsik Choi <[email protected]> wrote: > Hi folks, > > I'm very happy to see that our community is growing! Also, It's a pleasure > to discuss the Tajo 0.8.0 release. Recently, I've tested various features > in various contexts, and tried to figure out if there are any critical > problems. I think that there are only a few issues and we can release 0.8.0 > next week. If there are further issues to be solved before the 0.8.0 > release, feel free to suggest ideas. > > Also, I'd like to discuss our next roadmap. We are open to any suggestion > from users, contributors, and committers. Please fire away! > > I'm thinking that our next stage should focus on improving the way Tajo > runs in thousands of large cluster nodes and for a number of concurrent > users. The key issues associated with this include the following: > > * High availability > * Multi-tenancy scheduling > * More stability > * Improved shuffle > > The current work status is as follows. Min is working on Tajo's new > scheduler (TAJO-540) based on sparrow. I'll support him. As far as I know, > Alvin is working on TajoMaster HA (TAJO-704). Also, some guys including > myself are investigating and solving the issues which occur in large > clusters. These issues should be solved in order to make Tajo a complete > enterprise-ready production. > > In addition, there are some SQL feature support issues. Many analytic > problems require window functions. Also, in-subquery and scalar subquery > should be supported. So, I'd like to schedule them with high priority. In > my view, there will be very few SQL support issues if Tajo provides these > features. > > Besides those areas, David is working on a nested schema and its related > work (TAJO-710). I guess this will take quite a while because it requires a > lot of hard work. So, it would be great to schedule the nested schema > loosely. That's just my thoughts, anyhow. > > Aside from the discussion of our roadmap, I'd like to suggest that we need > to release more frequently after the 0.8.0 release. So far, there has been > a long period between each release because Tajo is undergoing heavy > development. By 'releasing early, releasing often', we will make more > tighter feedback loop between users and developers. > > I think that there are many additional many interesting issues to be > included in our roadmap. Feel free to suggest your idea. We will arrange > our short-term roadmap and long-term roadmap based on your suggestions. > > Thank you all so much for your contribution! > > Warm Regards, > Hyunsik
