I was testing with the number of jobs and was expecting to get the total I/O throughput for each different number of jobs The job numbers should have positive correlation with the total I/O throughput The test I have conducted in the SSD workstation is here below The result didnt make any sense because I/O throughput of 1 job is bigger than multiple number of jobs However when I test it in my macbook with the virtual box(with SSD configured),the result is different This is the FIO parameter that I have used in the test   filename=/dev/sdd    bs=4k    numjobs=1 ~ 64    iodepth=32    direct=1    ioengine=libaio    rw=read    runtime=20    group_reporting=1Is there something that I have done wrong? I believe I have used the parameters wrong on this case. 
Proper way to use FIO (Flexible IO tester) for I/O throughput
linux;linux kernel