Is cassandra-shuffle command in the trunk? Or it is only included in the Debian package? I don't find it in the trunk.
On Sat, Nov 3, 2012 at 2:18 AM, Eric Evans <eev...@acunu.com> wrote: > On Fri, Nov 2, 2012 at 12:38 AM, Manu Zhang <owenzhang1...@gmail.com> > wrote: > >> It splits into a contiguous range, because truly upgrading to vnode > >> functionality is another step. > > > > That confuses me. As I understand it, there is no point in having 256 > tokens > > on same node if I don't commit the shuffle > > This isn't exactly true. By-partition operations (think repair, > streaming, etc) will be more reliable in the sense that if they fail > and need to be restarted, there is less that is lost/needs redoing. > Also, if all you did was migrate from 1-token-per-node to 256 > contiguous tokens per node, normal topology changes (bootstrapping new > nodes, decommissioning old ones), would gradually work to redistribute > the partitions. And, from a topology perspective, splitting the one > partition into many contiguous partition is a no-op; it's safe to do > and there is no cost to speak of from a computational or IO > perspective. > > On the other hand, shuffling requires moving tokens around the > cluster. If you completely randomize placement, it follows that you > will need to relocate all of the clusters data, so it's quite costly. > It's also precedent setting, and not thoroughly tested yet. > > -- > Eric Evans > Acunu | http://www.acunu.com | @acunu >
