Thanks Andrey, However, I don't think I still have a problem. I modified the command From: >> fio --name=test --filename=#{dev.path} --rw=write --ioengine=libaio --direct=1 --io_limit=32M --size=100% --ba=4k --bs=512 To: fio --name=test --filename=#{dev.path} --rw=write:4k --ioengine=libaio --direct=1 --io_limit=32M --bs=512 The result is the runtime is too short. I guess fio stops as soon as it reaches the end of the device. However, I want it to repeat over and over again until io_limit is fully consumed. Note that the device is smaller than 32M (it is only 508B). So, it should repeat more than 60 times. How can I repeat the workload? Or, Building hand-made random map would suffice, I guess. - Akira On 9/23/14 11:05 PM, Andrey Kuzmin wrote: > Offset modifier under rw= should do the trick, consult > https://github.com/axboe/fio/blob/master/HOWTO for details. > > Best regards, > Andrey > Regards, > Andrey > > > On Tue, Sep 23, 2014 at 5:47 PM, Akira Hayakawa <ruby.wktk@xxxxxxxxx> wrote: >> Hi, >> >> I want to perform stride write access to a block device but >> I don't have a clue how I can do that. >> >> What I want to do is to perform a stride access that >> each write size is 1 sector and 7 sectors are apart between each writes. >> (i.e. Only the first sector of each 4KB block) >> >> For example, >> 0, 8, 16, 24, 32, ... >> >> And, it repeat over the device until certain amount of writes are accomplished. >> In my case, amount of 32MB to 508KB device. >> >> I consider the command below works like as I want but it doesn't actually. >> Instead, it looks performing ordinary 512KB seq write. >> fio --name=test --filename=#{dev.path} --rw=write --ioengine=libaio --direct=1 --io_limit=32M --size=100% --ba=4k --bs=512 >> >> My questions are: >> 1) How to perform stride write access in fio? >> 2) If fio is not a appropriate tool for this purpose, easy to fix? >> Or do you recommend other tool? >> >> - 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 -- 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