Once the total number of messages waiting to be processed exceeds the maximum queue length the session file will switch to a synchronous mode to catch up. This will not cause the application to experience synchronous logging behavior unless the publisher queue is also filled.
Requirements
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2