Solr indexing performance (shorter index cycles) may improve by increasing the number of threads used in the jobs that send data to Solr for indexing. The OOTB setting (1) may be too low. Take into consideration, the number of available cores on the node instance that is transmitting data to the Solr Master indexing server, and apply a factor of 1 - 1.5 x the number of available cores as a general guide.