Both Aspire and MongoDB are high memory consuming applications. Consider limiting the RAM they can allocate by looking into the MongoDB storage engine configuration and setting the Wired Tiger Cache size appropriately.
Be careful. JVM changes the pointers' size after 32GB, doubling them and affecting your RAM storage.
The number of available threads and open files are unlimited just for the root user. If you plan to set another user, check that the limits on both numbers.