Re: LBA selection in FIO

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

The hurdle I have is, how will I arrive at block size of 4k.
If LBA size is 4k, then write of 4 LBA will be 16k.
So if I say LBA count, I don't need to care of LBA size. But to
specify the size in bytes, I need to fetch the LBA size(for example
512, 520, 4096 etc.,) and arrive at the bytes required


I did try the buffer pattern of 0x0 and it doesn't work
fio throws out error of "failed parsing pattern `0x0`"

Regards,
Gnana

On Wed, Jan 3, 2018 at 12:17 PM, Sitsofe Wheeler <sitsofe@xxxxxxxxx> wrote:
> Hi Gnana,
>
> On 3 January 2018 at 17:47, Gnana Sekhar <kgsgnana2020@xxxxxxxxx> wrote:
>>
>> Basically I am looking to see if FIO has the below option
>> 1. Pass the LBA count as an argument. From your explanation my
>> understanding is currently FIO doesn't have that option
>
> Well I'm still unsure what LBA count means in this context. If my
> blocks are 512 bytes big and I want a single write to cover LBA 0 - 3
> then isn't the blocksize of 4k controlling the LBA count? Sorry to
> keep asking I just don't understand the request.
>
>> 2. On the buffer pattern I wasn't able to specify the buffer pattern
>> to be all 0(zero) but --buffer_pattern=1 works fine. Do I have to use
>> zero_buffers to fill buffers with zero and not buffer_pattern
>
> Hmm! 0 is going to be interpreted as "this option is unset". Does 0x0 work?
>
>> For option1, if I cant pass LBA count, my plan is to
>> get LBA size of the drive,
>> multiply the LBA size with lba count which will give me the size in bytes
>> pass the size with --size=x b  where x is the size obtained in above step
>
> Are you trying to do I/O "on the spot" (e.g. only do I/O to the exact
> same region for the whole job)? If so you can
>
> * Use offset (http://fio.readthedocs.io/en/latest/fio_doc.html#cmdoption-arg-offset
> ) and size (http://fio.readthedocs.io/en/latest/fio_doc.html#cmdoption-arg-size
> ) to limit the region you do I/O within
> * Have blocksize use a value of <x> and the rw=read:<-x>
> * Use rw_sequencer=identical and rw=read:<highnumberhere>
> (http://fio.readthedocs.io/en/latest/fio_doc.html#cmdoption-arg-rw-sequencer
> )
>
> ?
>
> --
> Sitsofe | http://sucs.org/~sits/
--
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



[Index of Archives]     [Linux Kernel]     [Linux SCSI]     [Linux IDE]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux SCSI]

  Powered by Linux