order of the steps of disclosed processes may be altered within the scope of the invention a detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate the principles of the invention the invention is described in connection with such embodiments but the invention is not limited to any embodiment the scope of the invention is limited only by the claims and the invention encompasses numerous alternatives modifications and equivalents numerous specific details are set forth in the following description in order to provide a thorough understanding of the invention these details are provided for the purpose of example and the invention may be practiced according to the claims without some or all of these specific details for the purpose of clarity technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily obscured fig1 is a block diagram illustrating one embodiment of a layered device i o architecture that includes a file system quiescing driver in this example the layered device i o architecture includes multiple layers of drivers 102 110 that drive a device 112 i o requests are received by file system quiescing driver 102 and processed before passing data associated with the request to layer 1 as used herein quiescing includes any process that makes a disk consistent such as flushing file system data in a cache to a disk quiescing is.