How much data and request load do you expect on this small cluster? If fairly light, fine. But if heavy, be careful.
Someone else can chime in if they have a more solid answer on how many CPU cores Cassandra needs, but less than two per node seems inappropriate unless load is extremely light since it precludes much in the way of concurrency. Maybe you might be better off just running a single node on this box as long as load is fairly light and then grow it to a full 6, 8, or 12 nodes when data and request load warrant. Note that 3 nodes at RF=3 does not give you any additional data capacity although it does triple your request load capacity. Six nodes is sort of the sweet spot, giving you HA with RF=3 and doubling data capacity with a bunch of nodes to handle load. -- Jack Krupansky On Tue, Dec 15, 2015 at 1:53 AM, Vladimir Prudnikov <v.prudni...@gmail.com> wrote: > > On 14 Dec 2015, at 21:40, Robert Coli <rc...@eventbrite.com> wrote: > > On Mon, Dec 14, 2015 at 3:46 AM, Vladimir Prudnikov <v.prudni...@gmail.com > > wrote: > >> [I want to run Cassandra on a single server] > > > I struggle to imagine the purpose of doing this. > > > Save money. I don’t have huge enterprise behind me nor investor’s money on > my bank account. I just created an app and want to launch it and see if it > is what users will use and pay for. Once I get users using it I can scale > my hardware. > > Is it hard to start with 3 nodes on one server running in docker and then > just move 2 nodes to the separate servers? > > > You are going to sign yourself up for repeated painful changes of RF, as > well as downtimes. As Michael says, you will get most of the cost of a > distributed database and none of the benefit. > > > I'm pretty sure the ABSOLUTE MINIMUM reasonabl(ish) deploy of cassandra is > RF=N=2. > > =Rob > > >