Hello all, I'm fairly new to fio and am trying to vary the ratio of sequential to random IO per job. I'm not sure if I'm reading the section of the HowTo on mixed IO types right or not . I'm trying to have the first job do 100% sequential access, the 2nd do 50% sequential/50% random, and the 3rd do 100% random. Below is the section of the How To that I'm referring to as well as a snip of my config. For the mixed io types, the default is to split them 50/50. For certain types of io the result may still be skewed a bit, since the speed may be different. It is possible to specify a number of IO's to do before getting a new offset, this is one by appending a ':<nr>' to the end of the string given. For a random read, it would look like 'rw=randread:8' for passing in an offset modifier with a value of 8. If the suffix is used with a sequential IO pattern, then the value specified will be added to the generated offset for each IO. For instance, using rw=write:4k will skip 4k for every write. It turns sequential IO into sequential IO with holes. See the 'rw_sequencer' option. [4k 70/30% R/W - 100% seq] bs=4k rw=rw rwmixread=70 rwmixwrite=30 stonewall [4k 70/30% R/W - 50% seq] bs=4k rw=randrw:2 rwmixread=70 rwmixwrite=30 stonewall [4k 70/30% R/W - 0% seq] bs=4k rw=randrw rwmixread=70 rwmixwrite=30 stonewall -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
