Hi, Ivan Let me try to explain. I think that there are 2 goals that are mostly applicable for prod systems: 1. I can agree with Dave that swap is not a good case for performance and disk resource. It is possible that other applications can consume memory that is free after Ignite was started. In this case if Ignite will be creating new pages in runtime, it can face with OOM.
2. Ignite user can create wrong configuration. For example, data region can exceed available memory by mistake or Ignite can be started on another server with less RAM. It can lead to catch OOM in runtime To summarize: Pre-allocation can detect listed issues on Ignite start by allocating OS RAM Im sure that this option have to be disabled by default, but user should have a choice for startup -- Sent from: http://apache-ignite-developers.2346864.n4.nabble.com/
