97 ms·

This seems to be the right product for loads of systems. I haven't seen much take up though.

by rb808 6y ago

logicslave 6y ago
It has significant operational load and complexity. Five node types, communicating with zookeeper
- mrits 6y ago
  With Kafka's removal of ZooKeeper I wonder if Druid could piggy back off of that to simplify their architecture. At least using some of the Kafka terminology would be a step in the right direction. I think even a hard dependency of Kafka would be better for the adoption rate than their current design.
  - doliveira 6y ago
    I don't know much about it other than what I've learned through the struggle of trying to set up a cluster. But why do so many projects depend on Zookeeper? What does it provide that couldn't be done through a embedded library? Seems like a lot of databases don't really need it. Is it worth the extra network dependency and operational complexity?
    - tomnipotent 6y ago
      > But why do so many projects depend on Zookeeper? Hadoop ecosystem legacy. Most companies adopting tech like Druid were already running Hadoop and had Zookeeper as a result. Probably made sense to take advantage of a reliable, or at least well-known, system.
      - 2bethere 6y ago
        Have an upvote.
    - mrits 6y ago
      A lot of tools (especially in Hadoop) were doing the same things. So the idea is to share all that logic in its own dedicated service. Like so many other things in software the tradeoffs had unforeseen consequences. What is an optimization for that community became baggage to the newcomers. I think HashiCorp is one of the worst offenders of this thought (even though I love them and use several of their tools)
    - hodgesrm 6y ago
      Your question could be rephrased: why do so many projects depend on an external store for distributed consensus? One answer is that coupling the consensus part of the system with parts that do active work results in harmful resource conflicts. Those resource conflicts can cause consensus algorithms to fail or take much longer to return answers. Example: Java VM clocks misbehave if the process can't get enough CPU. This can cause systems like ZK to lose quorum.
  - 2bethere 6y ago
    Maybe, the community is thinking about it. But probably not the most pressing problem to solve right now.
uptown 6y ago
Perhaps you've heard of a little video site called Netflix: https://netflixtechblog.com/how-netflix-uses-druid-for-real-time-insights-to-ensure-a-high-quality-experience-19e1e8568d06 https://netflixtechblog.com/how-netflix-uses-druid-for-real-...
blackswan101 6y ago
netflix, twitter, BT, Walmart I believe...

This seems to be the right product for loads of systems. I haven't seen much take up though.

by rb808 6y ago

This seems to be the right product for loads of systems. I haven't seen much take up though.

logicslave 6y ago

It has significant operational load and complexity. Five node types, communicating with zookeeper

mrits 6y ago
With Kafka's removal of ZooKeeper I wonder if Druid could piggy back off of that to simplify their architecture. At least using some of the Kafka terminology would be a step in the right direction. I think even a hard dependency of Kafka would be better for the adoption rate than their current design.
- doliveira 6y ago
  I don't know much about it other than what I've learned through the struggle of trying to set up a cluster. But why do so many projects depend on Zookeeper? What does it provide that couldn't be done through a embedded library? Seems like a lot of databases don't really need it. Is it worth the extra network dependency and operational complexity?
  - tomnipotent 6y ago
    > But why do so many projects depend on Zookeeper? Hadoop ecosystem legacy. Most companies adopting tech like Druid were already running Hadoop and had Zookeeper as a result. Probably made sense to take advantage of a reliable, or at least well-known, system.
    - 2bethere 6y ago
      Have an upvote.
  - mrits 6y ago
    A lot of tools (especially in Hadoop) were doing the same things. So the idea is to share all that logic in its own dedicated service. Like so many other things in software the tradeoffs had unforeseen consequences. What is an optimization for that community became baggage to the newcomers. I think HashiCorp is one of the worst offenders of this thought (even though I love them and use several of their tools)
  - hodgesrm 6y ago
    Your question could be rephrased: why do so many projects depend on an external store for distributed consensus? One answer is that coupling the consensus part of the system with parts that do active work results in harmful resource conflicts. Those resource conflicts can cause consensus algorithms to fail or take much longer to return answers. Example: Java VM clocks misbehave if the process can't get enough CPU. This can cause systems like ZK to lose quorum.
- 2bethere 6y ago
  Maybe, the community is thinking about it. But probably not the most pressing problem to solve right now.

uptown 6y ago

Perhaps you've heard of a little video site called Netflix: https://netflixtechblog.com/how-netflix-uses-druid-for-real-time-insights-to-ensure-a-high-quality-experience-19e1e8568d06 https://netflixtechblog.com/how-netflix-uses-druid-for-real-...

blackswan101 6y ago

netflix, twitter, BT, Walmart I believe...