DSpace, Fedora, and Greenstone are three widely used open source digital library systems. In this paper we report on scalability tests performed on these tools by ourselves and others. These range from repositories populated with synthetically produced data to real world deployment with content measured in millions of items. A case study is presented that details how one of the systems performed when used to produce fully-searchable newspaper collections containing in excess of 20 GB of raw text (2 billion words, with 60 million unique terms), 50 GB of metadata, and 570 GB of images.
