On Nov 21, 2012, at 9:11 AM, GIROLAMI Philippe <philippe.girol...@cegedim.fr> wrote:
> Hello, > We're working on integrating SolrCloud andwe're wondering whether issuing a > softCommit via Solrj forces the soft commit : > > a) only on the receiving core or > b) to the whole cluster and the receiving cores forwards the soft commit to > all replicas. The answer is b. > > If the answer is a), what is the best practice to ensure data is indeed > commited cluster-wide ? Commit is no longer what ensures durability in solrcloud. Because of the transactionlog, once a request is ack'd, it's in. Hard commits then become about relieving the memory pressure of the transactionlog, and soft commits are about visibility. Neither is required for durability. > If the answer is b), what would happen on a 1-replica setup if one commit > succeeded and the replica commit failed ? What's the reason the commit failed? Either a really bad problem and that node will need to be restarted and either won't answer requests or it will be asked to recover by the leader when sending it an update that failed. Because commits are not required for durability, it's probably not the issue that you think. - Mark