I get it and agree with you that FIO shouldn't be the limiting factor, but I don't get it why I am not getting sensible numbers when I increase the number of devices. Apparently, I am only interested in actual throughput FIO can drive my raid array, rather than ramdisk in this case. Thanks A. On Thu, Jul 3, 2014 at 1:45 PM, David Nellans <david@xxxxxxxxxxx> wrote: > On 07/03/2014 12:28 PM, Yuyang (Alex) Wang wrote: >> >> Carl, >> >> Specifying them as separate jobs will do what I expect. However, in >> this case, I am seeking to know how much performance and how many >> devices can a __single__ FIO process can drive. If my above >> configuration is correct, then, for some reason, the single process >> doesn't increase with more devices at its disposal, not as I have seen >> from another benchmark tool - which is puzzling. I am curious to >> understand why. >> >> Best, >> >> A. > > If you want to benchmark fio throughput or the block layer, not your actual > raid array, > then use a ramdisk. There are lots of flash devices out there now which > will push far > more than 1.4GB/s from a single device, rest assured fio isn't your > limitation here. > 1.4 GB/s with 1M block sizes isn't even 2k IOPS. fio pushes 500k IOPS > through the block layer > without issue, its not your limiting factor. -- 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
