4 ms·

So reading through this announcement, it seems the key to ANNA's speed is: local cache (in the form of the actor's mailbox) + background gossip The usual rest

So reading through this announcement, it seems the key to ANNA's speed is: local cache (in the form of the actor's mailbox) + background gossip The usual restrictions (and increases in latency) still apply when you want to make sure that something's actually written (quoruming) after you've written it, from what I can tell. Can someone explain to me why this is a step forward for the field -- I haven't yet read all the papers they linked to (including their ANNA papers), but this doens't seem to be one of those times where a bunch of disparate papers are combined into creating something truly groundbreaking? I feel like I must be missing the point

ricardobeat 9y ago
I don't think that's correct. The real key to its performance seems to be the usage of distributed lattices as data structures, and the ability to perform compile-time checks that guarantee the data will be eventually consistent, both of which allow code to be completely lock-free. This comes from the CALM paper cited in the article - lots of reading to do!
- doorbumper 9y ago
  I thought so before too, but after reading the paper again, I came to the same conclusion as the parent. The usage of distributed lattices is key, but it only works because it allows them to reduce messaging cost and gossip at background intervals. As far as I can tell, this means that you can receive a successfully written response, have that machine die , and all data within the last multicast period is lost. Therefore, it isn't suitable as a datastore, and the benchmarks are mostly worthless with the exception of Redis.
  - hardwaresofton 9y ago
    Super duper late, but I still haven't had time to read any of the papers (there are like 4 if I really want to get anywhere close to understanding their spin on gossip + the lattice thing) -- glad the discussion is still interesting though. I'm starting to think that the quorum strategy is something like a theoretical lower bound -- at least until someone brilliant figures out a way past it (or technology shifts in some gigantic way or something).
leventov 9y ago
Same thoughts, basically: https://news.ycombinator.com/item?id=16555741 https://news.ycombinator.com/item?id=16555741

ricardobeat 9y ago

I don't think that's correct. The real key to its performance seems to be the usage of distributed lattices as data structures, and the ability to perform compile-time checks that guarantee the data will be eventually consistent, both of which allow code to be completely lock-free. This comes from the CALM paper cited in the article - lots of reading to do!

doorbumper 9y ago
I thought so before too, but after reading the paper again, I came to the same conclusion as the parent. The usage of distributed lattices is key, but it only works because it allows them to reduce messaging cost and gossip at background intervals. As far as I can tell, this means that you can receive a successfully written response, have that machine die , and all data within the last multicast period is lost. Therefore, it isn't suitable as a datastore, and the benchmarks are mostly worthless with the exception of Redis.
- hardwaresofton 9y ago
  Super duper late, but I still haven't had time to read any of the papers (there are like 4 if I really want to get anywhere close to understanding their spin on gossip + the lattice thing) -- glad the discussion is still interesting though. I'm starting to think that the quorum strategy is something like a theoretical lower bound -- at least until someone brilliant figures out a way past it (or technology shifts in some gigantic way or something).

leventov 9y ago

Same thoughts, basically: https://news.ycombinator.com/item?id=16555741 https://news.ycombinator.com/item?id=16555741