Compressing and decompressing compressed index lists. One or more index lists include at least a portion of the list that is compressed. A method includes reading an entry from a list. The method further includes determining that the entry indicates the start of a compressed block of the list. The compressed block is compressed using a compression algorithm including a plurality of delta pointers. Each of the delta pointers point to data store entries by reference to a difference from a reference in a previous entry in the list. An entry size indicator is referenced. The entry size indicator is configured to indicate a memory storage size for a delta pointer, and the entry size indicator supports indications for all of fixed storage sizes, variable storage sizes, and run length encoding. The compressed block of the list is decompressed according to the entry size indicator.