> I wonder why not setting it to all the way down to 1 then? What's the key difference once you have so few vnodes?
4 tokens lets you have balanced clusters when they're small and imposes very little overhead when they get big. Using multiple tokens let's multiple nodes stream data to the new node, which helps keeps bootstrap times down. > And those are? That using 4 tokens by itself isn't enough, you need to start the cluster out in a manner that distributes the initial tokens, using the technique I listed. > Do you possibly know if the DSE-style option which doesn't require a keyspace to be there also works to allocate evenly distributed tokens for the very first seed node? I have no idea what DSE does, sorry. I don't have access to the source. Sounds like a question for their slack channel. On Sat, Sep 8, 2018 at 11:17 AM Oleksandr Shulgin < oleksandr.shul...@zalando.de> wrote: > On Sat, 8 Sep 2018, 14:47 Jonathan Haddad, <j...@jonhaddad.com> wrote: > >> 256 tokens is a pretty terrible default setting especially post 3.0. I >> recommend folks use 4 tokens for new clusters, >> > > I wonder why not setting it to all the way down to 1 then? What's the key > difference once you have so few vnodes? > > with some caveats. >> > > And those are? > > When you fire up a cluster, there's no way to make the initial tokens be >> distributed evenly, you'll get random ones. You'll want to set them >> explicitly using: >> >> python -c 'print( [str(((2**64 / 4) * i) - 2**63) for i in range(4)])' >> >> >> After you fire up the first seed, create a keyspace using RF=3 (or >> whatever you're planning on using) and set allocate_tokens_for_keyspace to >> that keyspace in your config, and join the rest of the nodes. That gives >> even distribution. >> > > Do you possibly know if the DSE-style option which doesn't require a > keyspace to be there also works to allocate evenly distributed tokens for > the very first seed node? > > Thanks, > -- > Alex > > -- Jon Haddad http://www.rustyrazorblade.com twitter: rustyrazorblade
