title: how to improve a large number of smaller files read and write speed or performance
body: <p>Yesterday,I asked the question at here:<a href="https://stackoverflow.com/questions/8692635/how-do-disable-disk-cache-in-c-sharp-invoke-win32-createfile-api-with-file-flag">how do disable disk cache in c# invoke win32 CreateFile api with FILE_FLAG_NO_BUFFERING</a>.</p>
  
  <p>In my performance test show(write and read test,1000 files and total size 220M),the <code>FILE_FLAG_NO_BUFFERING</code> can't help me improve performance and lower than .net default disk cache,since i try change <code>FILE_FLAG_NO_BUFFERING</code>  to <code>FILE_FLAG_SEQUENTIAL_SCAN</code> can to reach the .net default disk cache and faster little.</p>
  
  <p>before,i try use mongodb's gridfs feature replace the windows file system，not good(and i don't need to use distributed feature,just taste).</p>
  
  <p>in my Product,the server can get a lot of the smaller files(60-100k) on per seconds through tcp/ip,then need save it to the disk,and third service read these files once(just read once and process).if i use asynchronous I/O whether can help me,whether can get best speed and best low cpu cycle?. someone can give me suggestion?or i can still use FileStream class?</p>
  
  <p><strong>update 1</strong></p>
  
  <p>the <strong>memory mapped file</strong> whether can to achieve my demand.that all files write to one big file or more and read from it?</p>