+1 to lowering it. Thanks Jon for starting this.We should create a JIRA to find what other defaults we need revisit. (Please keep this discussion for "default token" only. )
On Fri, Sep 21, 2018 at 8:26 PM Jeff Jirsa <jji...@gmail.com> wrote: > Also agree it should be lowered, but definitely not to 1, and probably > something closer to 32 than 4. > > -- > Jeff Jirsa > > > > On Sep 21, 2018, at 8:24 PM, Jeremy Hanna <jeremy.hanna1...@gmail.com> > wrote: > > > > 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 > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@cassandra.apache.org > For additional commands, e-mail: dev-h...@cassandra.apache.org > >
