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I don't know a whole lot about Redis, so I'm struggling to understand what this is. Am I correct in saying that this is just the clustering mechanism? So I'd ne

• doyoubi 5y ago
  Yes, that's accurate. This project runs on top of Redis as Redis has already done a good job as a memory storage engine. And https://github.com/doyoubi/undermoon-operator https://github.com/doyoubi/undermoon-operator will help run it with Redis instances together, so you won't need to set them up manually. And yes, it can work with KeyDB in theory.
  • deleted 5y ago
    [deleted]
  • lrem 5y ago
    Is Redis still single-threaded? I thought that would become a bit of a problem by now.
    • doyoubi 5y ago
      Redis 6 has already supported multiple threads for IO. The memory storage engine is still inside a single thread but I think it's fine.
      • lrem 5y ago
        Do you mean that a single CPU can saturate the throughput of a machine's RAM? That's a bit surprising, given that current crop of Intel CPUs does non uniform memory access. Or, is that bandwidth so much above any I/O that it doesn't matter?
        • doyoubi 5y ago
          Nop. It's that a better solution would still be using multiple Redis instances on each physical server. Trying to support multi-threads in the storage engine requires complex synchronization implementation. Sharing nothing between each small instance achieves higher performance and is a lot simpler. Also, FULL SYNC between masters and replicas can be uncontrollable. And smaller memory size for each instance alleviates the performance impact from FULL SYNC.
          • ohthehugemanate 5y ago
            not to mention, multiple instances follows the indistry direction in horizontal scalability. Common advice when building for k8s style cloud environments is to target single core, n instances, to maximize scaling flexibility and atomicity.
      • throwaway81523 5y ago
        There is a parallel but less fancy reimplementation of Redis called Pedis: https://github.com/fastio/1store https://github.com/fastio/1store It's built using Seastar, which is sort of an ugh but cool unholy marriage of node.js and C++14 with an event loop per thread, and message passing between threads. It predates C++20 coroutines I guess, so you pass callbacks around like in Node using C++ lambdas. Maybe they have updated that by now. They have also done a version of memcached using DPDK. I don't see a Pedis one, but check out their memcached one (scroll down): http://seastar.io/ http://seastar.io/
        • doyoubi 5y ago
          Cool! Thanks for sharing.
        • EdwardDiego 5y ago
          Wow that's a product name horribly prone to typo/auto-correct awkwardness.
          • rubyist5eva 5y ago
            At first I was like, “heh, parallel redis so pedis”…then I said it out loud and I was like….oh my
        • derefr 5y ago
          > It's built using Seastar, which is sort of an ugh but cool unholy marriage of node.js and C++14 with an event loop per thread, and message passing between threads. It predates C++20 coroutines I guess, so you pass callbacks around like in Node using C++ lambdas. Maybe they have updated that by now. That seems like a lot of work just to badly recreate Erlang. (Which, yes, doesn’t let you define your own native data structures in-and-of-itself — but there’s always NIFs, e.g. https://blog.discord.com/using-rust-to-scale-elixir-for-11-million-concurrent-users-c6f19fc029d3 https://blog.discord.com/using-rust-to-scale-elixir-for-11-m....)