It's indeed not that easy to quantify. A lot of indexes get considerably smaller - whether and how much that increases performance hugely depends on whether tha

It's indeed not that easy to quantify. A lot of indexes get considerably smaller - whether and how much that increases performance hugely depends on whether that means your workload afterwards fits into memory. It also depends hugely whether there's any duplicates in the index (the benefits are much larger if there are). Some numbers are here https://www.postgresql.org/message-id/CAH2-WzmsK-1qVR8xC86DXv8U0cHwfPcuH6hhA740fCeEu3XsVg@mail.gmail.com https://www.postgresql.org/message-id/CAH2-WzmsK-1qVR8xC86DX... but there's a lot more details in other parts of this, and other threads. And for one of the other bree improvements, it hugely depends on how high your concurrency is, and whether your data is ordered in a sense, or not: https://www.postgresql.org/message-id/CAPpHfduAMDFMNYTCN7VMBsFg_hsf0GqiqXnt%2BbSeaJworwFoig%40mail.gmail.com https://www.postgresql.org/message-id/CAPpHfduAMDFMNYTCN7VMB...