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A database, if you are running Tomcat and the database on the same server
A reverse proxy, if you are also running this on the same server; although in general these will have a minor footprint across all resources (CPU, memory, storage) for most PhixFlow instances
Anti-virus, and other security and monitoring software; see note at the bottom of this page to make sure that any anti-virus software does not interfere with MariaDBMySQL
Tomcat will consume memory in addition to the assigned heap memory; you should allow a 20% overhead on the assigned memory.
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