LBA Size isn't 4k its 1 block, isn't it? LBA = logical block address (single address of 1 block not range). -----Original Message----- From: fio-owner@xxxxxxxxxxxxxxx [mailto:fio-owner@xxxxxxxxxxxxxxx] On Behalf Of Gnana Sekhar Sent: Wednesday, January 3, 2018 4:12 PM To: Sitsofe Wheeler <sitsofe@xxxxxxxxx> Cc: fio@xxxxxxxxxxxxxxx Subject: Re: LBA selection in FIO 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-seq > uencer > ) > > ? > > -- > 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 ��.n��������+%������w��{.n�������^n�r������&��z�ޗ�zf���h���~����������_��+v���)ߣ�
