Hi, I am writing a test with fio tool (2.0.8) and I am facing a problem. I just want to submit 512B random write to a block device. In my case, the size of the device is 2MB and the amount of writes (specified by --size option) is 32MB. like this (A line from device-mapper-test-suite. Is my command wrong?): ProcessControl.run("fio --name=test --filename=#{dev.path} --rw=randwrite --ioengine=libaio --direct=1 --size=#{@param[0]}m --bs=512") The problem is, the runtime is too short. The block device is just a single HDD so, it will be 30sec or so. But it's actually 3sec... My guess is that fio uses min(device size, param to --size) as the amount of writes here. To investigate it, I increased the size of the device to x10 and saw the runtime gets x10. My questions are: 1. Is my guess correct? 2. What shall I do to make fio work as I want it to do? Thanks, - Akira -- 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