http://seer.entsupport.symantec.com/docs/326236.htm
10. ArchiveListChunkThreshold
HKLM\SOFTWARE\KVS\Enterprise Vault\Directory\DirectoryService
Dword Value: ArchiveListChunkThreshold
Value data (Hex): 000003e8
Why? This registry key helps the administration of archives in the administration console, and will offer a small performance gain, by splitting the number of archives listed into subcontainers. For example with the best practice value of 1000, if you have 5000 mailbox archives you will get 5 subcontainers
https://www.linkedin.com/in/alex-allen-turl-07370146