Hi, The main thing that i am trying to do is to model the storScor in linux enviornment (https://github.com/Microsoft/StorScore/blob/master/recipes/write_impact_check.rcp). So there you can control the rate of the of the writes as per the % that is required. While running that on windows i can see that i can have different BS and rate defined for the runs achieving expected output. In the above mentioned case the RND_RD will be unconstrained (i.e. full BW they can achieve) but writes will be slowed to x% of RND_RD. In fio when e.g. SEQ_WR 10% and RND_RD 90%, with seq_wr rate capped at 10% of rnd rd (if rnd_rd was 40m) [SEQ_WR] rate=4m bs=128K rw=write flow=9 [RND_RD] rate=40m bs=4k rw=randread flow=-1 When i run this the output that comes back shows that SEQ_WR b/w is capped ~ 4m but RND_RD also gets severely hit for the IOPS+BW as it tried to put the total BW under <45m>. I want that RND_RD doesn't need to be capped and should run to it closest potential like I am see in storScor. Really appreciate for the support and helping me understand the limitations. On Wed, Jul 12, 2017 at 11:16 PM, Sitsofe Wheeler <sitsofe@xxxxxxxxx> wrote: > Hi, > > Please don't drop the fio mailing list CC / send email only to me as > it ends up in the wrong folder for me and you remove the ability for > others to answer your question or find it via search engines. Thanks! > > I think you're right - there would be an impact. However if SEQ_WR > were to go really slow (say, 9 IOPS a second) how else can the ratio > of SEQ_WR to RND_RD you requested be maintained other than by slowing > down RND_RD? By definition haven't you also bound the rates together? > > On 12 July 2017 at 22:13, abhishek koundal <akoundal@xxxxxxxxx> wrote: >> Looks like this wont be be able to control the rate if i want to just >> for write. Looks like it will impact the rate for the reads also , >> what do you think? >> [SEQ_WR] >> rw=write >> rate=0, 30m,0 >> flow=-1 >> [RND_RD] >> rw=randread >> flow=9 >> >> On Sun, Jul 9, 2017 at 7:05 AM, Sitsofe Wheeler <sitsofe@xxxxxxxxx> wrote: >>> Hi, >>> >>> On 7 July 2017 at 22:44, abhishek koundal <akoundal@xxxxxxxxx> wrote: >>>> >>>> Is there an easy way in FIO to have a mix workload which can do below >>>> config in single operation mode: >>>> >>>> 90% SEQ_WR >>>> 10% RND_RD >>> >>> I'd suggest using two threads to do this and then using flow >>> (http://fio.readthedocs.io/en/latest/fio_doc.html#cmdoption-arg-flow ) >>> to control how many turns each gets relative to the other: >>> >>> [SEQ_WR] >>> rw=write >>> flow=-1 >>> [RND_RD] >>> rw=randread >>> flow=9 >>> >>> This should work OK because you have a pair (but be aware flow doesn't >>> interact well with the number_ios option). If you need to balance more >>> than pairs of threads you will probably want to write a new fio >>> feature... > > -- > 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
