Hello Shawn. This question was raised because IMHO, apart from leader election, there are other load-generating activities such as all 10 solrj clients+solrCloudNodes listening to changes on clusterstate.json/state.json and downloading the whole file in case there is a change... And this would have happened on zk1 only if we did not shuffle... That's the theory. I could test this and see. On Sep 4, 2015 6:27 AM, "Shawn Heisey" <apa...@elyograg.org> wrote:
> On 9/3/2015 9:47 PM, Arcadius Ahouansou wrote: > > Let's say we have 10 SolrJ clients all configured with > > zkhost=zk1:port,zk2:port,zk3:port > > > > For each of the 10 SolrJ clients, would it make a difference in term of > > load on zk1 (the server on the list) if we shuffle around the order of > the > > ZK servers in zkHost or is it all the same? > > > > I would have thought that shuffling would lower load on zk1. > > I don't think this is going to make much difference. Here's why, > assuming that my understanding of how it all works is correct: > > One of the things zookeeper does is manage elections. It helps figure > out which member of a cluster is the leader. I think Zookeeper uses > this concept internally, too. One of the hosts in the ensemble will be > elected to be the leader, which accepts all input and replicates it to > the other members of the cluster. All of the clients will be talking to > the leader first, no matter what order the hosts are listed. > > If my understanding of how this works is flawed, then what I just said > is probably wrong. > > Thanks, > Shawn > >
