In this session we'll unravel the intricacies of PostgreSQL's internal data organisation, shedding light on the Free Space Map (FSM) mechanism. Delving into the heart of PostgreSQL's data architecture, we'll explore ways to strategically reorganise the data model capitalising on data alignment within blocks. The goal? To demonstrate techniques that not only optimise disk space usage but also enhance memory efficiency, potentially leading to significant cost savings and performance improvements. Discover the art of aligning data inside blocks, a crucial facet often overlooked in PostgreSQL optimisation. By strategically aligning data, we can wield the power to reduce the footprint of stored information on both disk and memory. As we navigate through practical examples and insightful strategies, you'll gain a new understanding of how these optimisations directly impact your budgetary considerations and system performance.