[ovirt-users] Re: Useless disk statistics API

On Wed, Jun 13, 2018 at 10:43 AM, Hari Prasanth Loganathan < hariprasanth.l(a)msystechnologies.com&gt; wrote: > Hi Yedidyah, > > I tried the read also, same result 0, > > > > > You keep reading virtual devices that read only from the kernel/memory... Please try reading from your disk. It's likely /dev/sda, or you can check using e.g. 'df /', 'lsblk', etc. And please check with vmstat/iostat that you see the reads. If you don't, try until you do. Only then check what oVirt has to say. Best regards, > On Wed, Jun 13, 2018 at 12:54 PM, Yedidyah Bar David <didi(a)redhat.com&gt; > wrote: > >> On Wed, Jun 13, 2018 at 9:53 AM, Hari Prasanth Loganathan < >> hariprasanth.l(a)msystechnologies.com&gt; wrote: >> >>> Hi Yedidyah, >>> >>> >>> *I tried running the 'dd if=/dev/zero of=/root/hari/test' and I >>> received the following output in VM oVirt console and meanwhile I checked >>> this API >>> https://172.30.60.42/ovirt-engine/api/disks/f78c8adf-23f9-4f52-a29b-0de3d... >>> <https://172.30.60.42/ovirt-engine/api/disks/f78c8adf-23f9-4f52-a29b-0de3d... >>> and the value is received as '0' always * >>> >>> >>> *where, * >>> * f78c8adf-23f9-4f52-a29b-0de3d844652e - disk ID attached to that VM* >>> >>> >>> >>> >>> >>> *Anything wrong? * >>> >> >> You only wrote 300 MB, are you sure it was enough to cause an actual >> write (and not cached)? >> >> Did you check vmstat/iostat? >> >> Perhaps try reading instead of writing. >> >> dd if=/dev/somedev of=/dev/null >> >> >>> >>> *Thanks,* >>> >>> *Hari * >>> >>> >>> >>> >>> >>> >>> On Wed, Jun 13, 2018 at 11:56 AM, Yedidyah Bar David <didi(a)redhat.com&gt; >>> wrote: >>> >>>> On Wed, Jun 13, 2018 at 8:45 AM, Hari Prasanth Loganathan >>>> <hariprasanth.l(a)msystechnologies.com&gt; wrote: >>>> > Hi Yedidyah, >>>> > >>>> > Thanks for your response. I also tried creating the file, writing >>>> some >>>> > content to the VM guest console. Still, I didn't see any increase in >>>> the >>>> > values, It is always 0. >>>> >>>> Not sure I understand. "Creating the file" - which one? >>>> >>>> Perhaps try something like: >>>> >>>> dd if=/dev/zero of=/root/myfile1 >>>> >>>> In any case, please test that the OS sees your IO. Use e.g. vmstat, >>>> iostat >>>> or something like that. oVirt (and metrics) will only show what the OS >>>> reports - if you see there '0', that's what you should get in metrics. >>>> >>>> Best regards, >>>> >>>> > >>>> > >>>> > >>>> > On Wed, Jun 13, 2018 at 10:58 AM, Yedidyah Bar David < >>>> didi(a)redhat.com&gt; >>>> > wrote: >>>> >> >>>> >> On Tue, Jun 12, 2018 at 1:24 PM, Hari Prasanth Loganathan >>>> >> <hariprasanth.l(a)msystechnologies.com&gt; wrote: >>>> >> > Hi Team, >>>> >> > >>>> >> > I use the following API to get the disk statistics as per the >>>> oVirt rest >>>> >> > API >>>> >> > documentation. >>>> >> > >>>> >> > >>>> >> > http://ovirt.github.io/ovirt-engine-api-model/4.2/#types/dis >>>> k/links/statistics >>>> >> > >>>> >> > >>>> >> > >>>> >> > https://172.30.X.X/ovirt-engine/api/disks/f78c8adf-23f9-4f52 >>>> -a29b-0de3d844652e/statistics >>>> >> > >>>> >> > >>>> >> > { >>>> >> > "statistic": [ >>>> >> > { >>>> >> > "kind": "gauge", >>>> >> > "type": "decimal", >>>> >> > "unit": "bytes_per_second", >>>> >> > "values": { >>>> >> > "value": [ >>>> >> > { >>>> >> > "datum": 0 >>>> >> > } >>>> >> > ] >>>> >> > }, >>>> >> > "disk": { >>>> >> > "href": "/ovirt-engine/api/disks/f78c8 >>>> adf-23f9-4f52-a29b-0de3d844652e", >>>> >> > "id": "f78c8adf-23f9-4f52-a29b-0de3d844652e" >>>> >> > }, >>>> >> > "name": "data.current.read", >>>> >> > "description": "Read data rate", >>>> >> > "href": >>>> >> > >>>> >> > "/ovirt-engine/api/disks/f78c8adf-23f9-4f52-a29b-0de3d844652 >>>> e/statistics/33b9212b-f9cb-3fd0-b364-248fb61e1272", >>>> >> > "id": "33b9212b-f9cb-3fd0-b364-248fb61e1272" >>>> >> > }, >>>> >> > { >>>> >> > "kind": "gauge", >>>> >> > "type": "decimal", >>>> >> > "unit": "bytes_per_second", >>>> >> > "values": { >>>> >> > "value": [ >>>> >> > { >>>> >> > "datum": 0 >>>> >> > } >>>> >> > ] >>>> >> > }, >>>> >> > "disk": { >>>> >> > "href": "/ovirt-engine/api/disks/f78c8 >>>> adf-23f9-4f52-a29b-0de3d844652e", >>>> >> > "id": "f78c8adf-23f9-4f52-a29b-0de3d844652e" >>>> >> > }, >>>> >> > "name": "data.current.write", >>>> >> > "description": "Write data rate", >>>> >> > "href": >>>> >> > >>>> >> > "/ovirt-engine/api/disks/f78c8adf-23f9-4f52-a29b-0de3d844652 >>>> e/statistics/2f23addd-4ebd-3d82-a449-c28778bc33eb", >>>> >> > "id": "2f23addd-4ebd-3d82-a449-c28778bc33eb" >>>> >> > } >>>> >> > ] >>>> >> > } >>>> >> > >>>> >> > >>>> >> > Unfortunately, the values are always coming as '0'. >>>> >> > >>>> >> > Steps to reproduce : >>>> >> > >>>> >> > 1) I logged into the VM console and run the following command to >>>> copy >>>> >> > the >>>> >> > file and I see the write rate is 300mb/sec >>>> >> > >>>> >> > dd if=/dev/zero of=/dev/null >>>> >> >>>> >> This command does not access the disk. Perhaps try to read or write >>>> to >>>> >> one, then check stats. >>>> >> >>>> >> Best regards, >>>> >> >>>> >> > >>>> >> > 2) During this time, I am trying to execute this API and >>>> receiving as 0 >>>> >> > always. >>>> >> > >>>> >> > Is this API useless? >>>> >> > >>>> >> > Thanks, >>>> >> > Hari >>>> >> > >>>> >> > _______________________________________________ >>>> >> > Users mailing list -- users(a)ovirt.org >>>> >> > To unsubscribe send an email to users-leave(a)ovirt.org >>>> >> > Privacy Statement: https://www.ovirt.org/site/privacy-policy/ >>>> >> > oVirt Code of Conduct: >>>> >> > https://www.ovirt.org/community/about/community-guidelines/ >>>> >> > List Archives: >>>> >> > >>>> >> > https://lists.ovirt.org/archives/list/users@ovirt.org/messag >>>> e/7TGIUQ2REOMSTJBGD3OPY5RE2KOSSFWM/ >>>> >> > >>>> >> >>>> >> >>>> >> >>>> >> -- >>>> >> Didi >>>> > >>>> > >>>> >>>> >>>> >>>> -- >>>> Didi >>>> >>> >>> >> >> >> -- >> Didi >> > > -- Didi