On 5/5/2015 1:15 PM, Rishi Easwaran wrote: > Thanks for clarifying lucene segment behaviour. We don't trigger optimize > externally, could it be internal solr optimize? Is there a setting/ knob to > control when optimize occurs.
Optimize never happens automatically, but *merging* does. An optimize is nothing more than a forced merge down to one segment. There is a merge policy, consulted anytime a new segment is created, that decides whether any automatic merges need to take place and what segments will be merged. That merge policy can be configured in solrconfig.xml. > The behaviour we see multiple huge directories for the same core. Till we > figure out what's going on, the only option we are left with it is to clean > up the entire index to free up disk space, and allow a replica to sync from > scratch. If multiple index directories exist after replication, there was either a problem that prevented the rename and deletion of the directories (common on Windows, less common on UNIX variants like Linux), or you're running into a bug. Unless you are performing maintenance or a machine goes down, index recovery (replication) should *not* be happening during normal operation of a SolrCloud cluster. Frequent index recoveries usually mean that there's a performance problem. Solr performs better on bare metal than on virtual machines. Thanks, Shawn
