There are a couple of ways to trigger a commit command in Solr. The easiest way is via a URL:
(Replace localhost:8983 with your Solr url and )
But you can also commit using the Documents option from the Admin UI. Simply navigate to Documents, using this URL:
And select Solr Command (raw XML orJSON), adding the command
<commit> true </commit>
Submit Document! It just works. And if you are using SolrCloud, the command goes to everyone.