Magento CE Blast Search Lucene Config

General information for the website: Online store
Description of requirements/features: We have a Magento 1.9.2.4 site running on nginx.
We have installed Blast Search Lucene and found the search facility to be fantastic, however the performance is terrible. Within hours our site crashes, needing a nginx restart. As soon as we disable the module performance returns to normal, around 20% CPU usage.
Specific technologies required: nginx
Extra services needed: 3rd party integration, Optimization
Extra notes: I'm after someone who has experience directly with the module and possible configuration options we can try in order to get it to run smoothly.