Hi Yes that is correct. The drive is showing : 2000398934016 and its not exact multiple of 128K So do we think this is how the tool will behave or we have a bug here? On Wed, Mar 7, 2018 at 12:17 AM, Sitsofe Wheeler <sitsofe@xxxxxxxxx> wrote: > Hi, > > What does > blockdev --getsize64 /dev/nvme0n1 > say? I'm going to guess that whatever number comes out is not an exact > multiple of 128Kbytes... > > On 7 March 2018 at 00:58, abhishek koundal <akoundal@xxxxxxxxx> wrote: >> Sitsofe, >> here is the log file when the size parameter is not give. >> command line will be : >> fio --name=global --time_based --direct=1 --norandommap >> --randrepeat=0 --buffered=0 --refill_buffers --name=job >> --ioengine=libaio --group_reporting --filename=/dev/nvme0n1 >> --numjobs=1 --iodepth=128 --bs=128k --rw=rw --rwmixread=70 >> --runtime=10800 --write_iops_log=wr.log -write_lat_log=wr.clat.log >> --log_avg_msec=1000 >> >> On Tue, Mar 6, 2018 at 2:28 PM, abhishek koundal <akoundal@xxxxxxxxx> wrote: >>> Sure Sitsofe >>> fio --name=global --time_based --size=100% --direct=1 --norandommap >>> --randrepeat=0 --buffered=0 --refill_buffers --name=job >>> --ioengine=libaio --group_reporting --filename=/dev/nvme0n1 >>> --numjobs=1 --iodepth=128 --bs=128k --rw=rw --rwmixread=70 >>> --runtime=10800 --write_iops_log=wr.log -write_lat_log=wr.clat.log >>> --log_avg_msec=1000 >>> >>> On Tue, Mar 6, 2018 at 1:23 PM, Sitsofe Wheeler <sitsofe@xxxxxxxxx> wrote: >>>> An example of an engine that can't deduce a size by itself is the null >>>> engine. Most file based engines (e.g. pvsync, sync, libaio) are able >>>> to. >>>> >>>> I'd really have to see the exact jobs that were run (i.e. the complete >>>> command line and fio job file if there was one) and the exact output >>>> that you mention showed the problem to say more. For example you say >>>> 2TBytes but that's probably not granular enough. What is more >>>> interesting is the size of the disk in bytes (from Linux's >>>> perspective) because I'd need to know exactly what rounding occured to >>>> understand what happened. >>>> >>>> On 6 March 2018 at 20:28, abhishek koundal <akoundal@xxxxxxxxx> wrote: >>>>> Sitsofe >>>>> The engine used is the libaio. I hope this helps. >>>>> Can you elaborate on the ioengine part which are able to query the >>>>> file/disk size and which wont be able to ? (I generally use libaio for >>>>> QD>1) >>>>> >>>>> On Tue, Mar 6, 2018 at 11:47 AM, abhishek koundal <akoundal@xxxxxxxxx> wrote: >>>>>> Hi, >>>>>> The workload I used was SEQ_MX 70/30 BS 128 QD 128 >>>>>> FIO used 3.1 >>>>>> Drive SKU = 2TB >>>>>> >>>>>> On Tue, Mar 6, 2018 at 11:43 AM, abhishek koundal <akoundal@xxxxxxxxx> wrote: >>>>>>> Hi, >>>>>>> The workload I used was SEQ_MX 70/30 BS 128 QD 128 >>>>>>> FIO used 3.1 >>>>>>> >>>>>>> On Tue, Mar 6, 2018 at 11:11 AM, Sitsofe Wheeler <sitsofe@xxxxxxxxx> wrote: >>>>>>>> >>>>>>>> On 6 March 2018 at 19:02, Sitsofe Wheeler <sitsofe@xxxxxxxxx> wrote: >>>>>>>> > Hi, >>>>>>>> > >>>>>>>> > On 6 March 2018 at 18:52, abhishek koundal <akoundal@xxxxxxxxx> wrote: >>>>>>>> >> All >>>>>>>> >> If the size parameter is not given for the runs, how does the tool >>>>>>>> >> decide what % (LBA span) needs to be written on the drive? >>>>>>>> > >>>>>>>> > It will query the disk/file for its size (but this depends on the >>>>>>>> > ioengine being able to do that and not all do/can). >>>>>>>> > >>>>>>>> >> Reason I am asking as I see different data for the same workloads when >>>>>>>> >> size=100% and no size parameter used. >>>>>>>> > >>>>>>>> > Hmm this sounds like it might be due to a rounding issue - what size >>>>>>>> > is your disk and what job were you running? >>>>>>>> >>>>>>>> https://github.com/axboe/fio/blob/master/filesetup.c#L1039-L1048 shows >>>>>>>> that when in setup_files() using a size set in percent will round the >>>>>>>> io_size down to the minimum block size whereas not setting size at all >>>>>>>> looks like it will pass the determined size straight through >>>>>>>> unrounded. I'm not sure what job you would see the difference on - >>>>>>>> perhaps one that did backwards I/O? >>>> >>>> -- >>>> Sitsofe | http://sucs.org/~sits/ >>> >>> >>> >>> -- >>> Life is too short for silly things so invest your time in some >>> productive outputs!! >> >> >> >> -- >> Life is too short for silly things so invest your time in some >> productive outputs!! > > > > -- > Sitsofe | http://sucs.org/~sits/ -- Life is too short for silly things so invest your time in some productive outputs!! -- 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
