I would like to write my own version of Microsoft Live labs pivot.http://www.getpivot.com/ For this i will use realtime texture streaming technology like John Carmack did for doom4. But i would like to use Windows vista SetFileBandwidthReservation api to have the best throughput possible. For example // reserve bandwidth of 200 bytes/sec result = SetFileBandwidthReservation( hFile, 1000, 200, FALSE, &transferSize, &outstandingRequests ); What i dont understand is the lpTransferSize and lpNumOutstandingRequests return parameters. How should i next read the file for this to be the most worth it. Should i do exactly lpNumOutstandingRequests number of request of size lpTransferSize. Or can i do one synchronous request bigger than lpTransferSize.