Recently Alfresco has released its Scalability Blueprint for Alfresco One 5.1, where Nathan McMinn explores different deployment scenarios and makes a deep analysis on grained data extracted with Alfresco Benchmark tool.
BM 3 Estimated Monthly Bill
BM 6 Estimated Monthly Bill
BM 4 Estimated Monthly Bill
A company managing 1 billion documents, which is the volume tested with BM4, will consider worth enough this bill :)