On 10/21/2014 05:54 PM, Michael Mattsson wrote: > Hey, > I'm trying to get predictable output from --status-interval. I believe > there's some output racing going on and can't think of a way of > working around it at this point. Is there a way to redirect > --status-interval to a separate file and have the summary go to > --output? That would be useful. > > Anyhow. > > Attached is a --side-by-side diff by a custom --minimal parser, this > is the command line used: fio --minimal --direct=1 --group_reporting > --filesize=100m --norandommap --blocksize=32k --time_based --iodepth=1 > --ramp_time=0 --ioengine=libaio --status-interval=5 > --percentage_random=100 --name=randrw-workload --rw=randrw > --rwmixread=0 --numjobs=2 --filename=/fut1/rs-dev2_2:/fut2/rs-dev2_2 > --runtime=60 --output fio_w.dat > > What happens is that intermittently I get a <1s splurge on the last > line which is suppose to be final output but it screws up the summary > fields, more explictly: > > Bandwidth KB > IOPS > Runtime (ms) > > Sometime it happens with this workload but it happens more > infrequently: fio --minimal --direct=1 --group_reporting > --filesize=100m --norandommap --blocksize=32k --time_based --iodepth=1 > --ramp_time=0 --ioengine=libaio --status-interval=5 > --percentage_random=100 --name=rainscaler-randrw --rw=randrw > --rwmixread=100 --numjobs=2 --filename=/fut1/rs-dev2_1:/fut2/rs-dev2_1 > --runtime=60 --output fio_r.dat > > What is good to know here is that both these run in parallel as two > independent fio jobs on the same host if there is some communication > between fio processes that are run independently on the same host that > promotes this behavior. I can't use /tmp/fio-dump-status as there will > be a race between master processes who unlink the file first. > > fio-2.1.4 and fio-2.1.13 on CentOS 6.5. Can you see if it works better if you revert commit 83f7b64ea773? -- Jens Axboe -- 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
