I agree that it should be lowered. What I’ve seen debated a bit in the past is the number but I don’t think anyone thinks that it should remain 256.
> On Sep 21, 2018, at 7:05 PM, Jonathan Haddad <j...@jonhaddad.com> wrote: > > One thing that's really, really bothered me for a while is how we default > to 256 tokens still. There's no experienced operator that leaves it as is > at this point, meaning the only people using 256 are the poor folks that > just got started using C*. I've worked with over a hundred clusters in the > last couple years, and I think I only worked with one that had lowered it > to something else. > > I think it's time we changed the default to 4 (or 8, up for debate). > > To improve the behavior, we need to change a couple other things. The > allocate_tokens_for_keyspace setting is... odd. It requires you have a > keyspace already created, which doesn't help on new clusters. What I'd > like to do is add a new setting, allocate_tokens_for_rf, and set it to 3 by > default. > > To handle clusters that are already using 256 tokens, we could prevent the > new node from joining unless a -D flag is set to explicitly allow > imbalanced tokens. > > We've agreed to a trunk freeze, but I feel like this is important enough > (and pretty trivial) to do now. I'd also personally characterize this as a > bug fix since 256 is horribly broken when the cluster gets to any > reasonable size, but maybe I'm alone there. > > I honestly can't think of a use case where random tokens is a good choice > anymore, so I'd be fine / ecstatic with removing it completely and > requiring either allocate_tokens_for_keyspace (for existing clusters) > or allocate_tokens_for_rf > to be set. > > Thoughts? Objections? > -- > Jon Haddad > http://www.rustyrazorblade.com > twitter: rustyrazorblade --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@cassandra.apache.org For additional commands, e-mail: dev-h...@cassandra.apache.org
