Greetings NTDEBUGGING community, Bob here again, and today I would like to let everyone know about a new feature implemented in the STORPORT.SYS binaries released in the following KB articles:· KB 979764 (Windows Server 2008) · KB 978000 (Windows Server 2008 R2) Beginning with these new versions, it is now possible to measure timing statistics for requests made to a system’s disk unit. These measurements are taken at the lowest possible level of OS interaction with the storage adapter hardware, making it much easier to diagnose storage performance issues. The measurements are taken from the port driver, STORPORT.SYS, via ETW (Event Tracing for Windows). Windows drivers are implemented in a layered architecture, so in our case the STORPORT driver interfaces directly with the adapter or miniport driver. The STORPORT driver is responsible for managing requests and queues, and providing other upper level functions. Each miniport driver is specific to a particular storage adapter card, and knows how to deliver requests to the disk unit over the transport medium, like fibre channel for instance. Configuring and Starting STORPORT ETW LoggingTo measure storage performance, the user enters a threshold value via the GUI interface. (This can be scripted as well; see KB 978000 for details.) When an I/O time is equal to or greater than the entered threshold, an event 13 is written to the ETW log. Here is a walkthrough to enable this feature via the GUI:Click Start, type “perfmon”, and press ENTER to start Performance Monitor.Read more: Ntdebugging Blog