This study analyzes the performance of the storage structures and algorithms employed in three experimental database storage systems - EXODUS, starburst, and EOS - for managing large unstructured general-purpose objects. all three mechanisms are segment-based in that large object is stored in a sequence of segments, each consisting of physically contiguous disk blocks. to analyze the algorithms we measured object creation time, sequential scan time, storage utilization in the presence of updates, and the I/O cost of random reads, inserts, and deletes.