http://developers.de/blogs/damir_dobric/archive/2010/11/18/comparing-etw-file-and-eventlog-logging-speed.aspxThe Windows Server AppFabric uses Event Tracing for Windows to when collecting events. That means there are several components in system like WCF, which trace huge amount of data into ETW based processor buffers. Following diagrams show average resultenCommunityServer 2008 SP1 (Build: 30619.63)