The "Install MongoDB on Amazon EC2" page has great step by step instructions for setting up on ec2 but it doesn't include the steps to set the correct ulimit, readahead or numa settings so someone who follows this page step by step may miss those recommendations. This page should be updated to adds steps to set ulimit, readahead and numa as shown in http://docs.mongodb.org/manual/administration/ulimit/ and http://docs.mongodb.org/manual/administration/production-notes/.