For certain types of io the result may still be skewed a bit,
since the speed may be different.
+randrepeat=bool For random IO workloads, seed the generator in a predictable
+ way so that results are repeatable across repetitions.
+
size=siint The total size of file io for this job. This may describe
the size of the single file the job uses, or it may be
divided between the number of files in the job. If the