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!! -- 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
