Try to use more storages to read and write
1) Every 8 sec the exportd chooses the optimum distribution for the next file
   to create. The next files will use an other distribution in order to use
   more storages.
   eg:
   storages are               0,1,2,3,4,5
   optimum distibution is     0,1,2,3
   1rst created file will get 0,1,2,3
   2nd file will get            1,2,3,0
   3rd file will get              2,3,0,1

2) The storcli reads from every first foward storages of a distribution.
   eg:
   If distibution is 0,1,2,3 first read will be asked to 0&1, 2nd one on
   1&2, 3rd on 2&0 and so on.