Heap size and Solr 4.3

[Marcello Lorenzi]

Hi All,
we have deployed on our production environment a new Solr 4.3 instance 
(2 nodes with SolrCloud) but this morning one node gone on outofmemory 
status and we have noticed that the JVM uses a lot of Old Gen space 
during the normal lifecycle.

What are the items that improve this high usage of Heap?

Thanks,
Marcello