When you use SFTP adapter to process many files and list many files/folders during receive in Microsoft BizTalk Server 2013, memory leak occurs over time. The degree and time of memory leak depends on the number of SFTP receive locations, their settings, and the contents on the SFTP server.
Cumulative update information
This issue was first fixed in the following cumulative update of BizTalk Server:
To work around this issue, reduce the number of additional files and folders (not being picked up, but listed every time) in the receive location polling folder.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For information about the service packs and cumulative update list for BizTalk Server, see KB 2555976: Service pack and cumulative update list for BizTalk Server.
For more information about BizTalk Server hotfixes, see KB 2003907: Information about BizTalk hotfixes and cumulative update support.