Multiple Sequential Reader vs Multiple Random Reader
===============================================
Vanilla CFQ
-----------------------------------
[Multiple Sequential Reader]        [Multiple Random Reader]            
nr  Agg-bandw Max-latency Agg-iops  nr  Agg-bandw Max-latency Agg-iops  
16  13883KB/s 1740K usec  3464      1   10KB/s    3226 msec   2         
16  12805KB/s 1750K usec  3192      2   30KB/s    3461 msec   6         
16  11529KB/s 2018K usec  2877      4   59KB/s    3937 msec   13        
16  9310KB/s  2557K usec  2327      8   102KB/s   3336 msec   23        
16  9953KB/s  2539K usec  2486      16  491KB/s   2951K usec  115       

IO scheduler controller + CFQ
-----------------------------------
[Multiple Sequential Reader]        [Multiple Random Reader]            
nr  Agg-bandw Max-latency Agg-iops  nr  Agg-bandw Max-latency Agg-iops  
16  6390KB/s  3352K usec  1590      1   222KB/s   232K usec   55        
16  6342KB/s  3440K usec  1579      2   214KB/s   554K usec   53        
16  6199KB/s  3420K usec  1542      4   180KB/s   1380K usec  43        
16  6500KB/s  3395K usec  1618      8   154KB/s   3165 msec   35        
16  6364KB/s  3441K usec  1586      16  145KB/s   5753 msec   29        

dm-ioaband + CFQ
-----------------------------------
[Multiple Sequential Reader]        [Multiple Random Reader]            
nr  Agg-bandw Max-latency Agg-iops  nr  Agg-bandw Max-latency Agg-iops  
16  10818KB/s 1373K usec  2698      1   33KB/s    1242K usec  8         
16  7909KB/s  1385K usec  1971      2   88KB/s    1901K usec  21        
16  2484KB/s  2053K usec  613       4   293KB/s   2421K usec  71        
16  1591KB/s  3042K usec  389       8   904KB/s   3215K usec  223       
16  1863KB/s  2247K usec  457       16  1187KB/s  3191K usec  290