zram does not support direct IO (tested, indeed fails). What I do is host the VMs there, though - this is working - but I'm using Lago (and not oVirt). does oVirt need direct IO for the temp disks? I thought we are doing them on the libvirt level?
This is the command I use: sudo modprobe zram num_devices=1 && sudo zramctl --find --size 12G && sudo mkfs.xfs -K /dev/zram0 && sudo mount -o nobarrier /dev/zram0 /home/zram && sudo chmod 777 /home/zram And then I run lago with: ./run_suite.sh -o /home/zram basic_suite_master Y. On Thu, Sep 29, 2016 at 10:47 AM, Evgheni Dereveanchin <edere...@redhat.com> wrote: > Hi Yaniv, > > this is a physical server with work directories > created on a zRAM device, here's the patch: > https://gerrit.ovirt.org/#/c/62249/2/site/ovirt_jenkins_ > slave/templates/prepare-ram-disk.service.erb > > I'll still need to read up on this but the only > slave having this class (ovirt-srv08) is now offline > and should not cause issues. I tested on VM slaves > and did not see errors from the dd test command you provided. > > Please tell me if you see errors on other nodes and I'll > check what's going on but it must be something else than RAM disks. > > Regards, > Evgheni Dereveanchin > > ----- Original Message ----- > From: "Yaniv Kaul" <yk...@redhat.com> > To: "Evgheni Dereveanchin" <edere...@redhat.com> > Cc: "infra" <in...@ovirt.org>, "devel" <devel@ovirt.org>, "Eyal Edri" < > ee...@redhat.com>, "Nir Soffer" <nsof...@redhat.com> > Sent: Thursday, 29 September, 2016 9:32:45 AM > Subject: Re: [ovirt-devel] [VDSM] All tests using directio fail on CI > > On Sep 29, 2016 10:28 AM, "Evgheni Dereveanchin" <edere...@redhat.com> > wrote: > > > > Hi, > > > > Indeed the proposed dd test does not work on zRAM slaves. > > Can we modify the job not to run on nodes with ram_disk label? > > Are those zram based or ram based *virtio-blk* disks, or zram/ram disks > within the VMs? > The former should work. The latter - no idea. > > > > > The node will be offline for now until we agree on what to do. > > An option is to abandon RAM disks completely as we didn't find > > any performance benefits from using them so far. > > That's very surprising. On my case it doubles the performance, at least. > But I assume my storage (single disk) is far slower than yours. > Y. > > > > > Regards, > > Evgheni Dereveanchin > > > > ----- Original Message ----- > > From: "Eyal Edri" <ee...@redhat.com> > > To: "Nir Soffer" <nsof...@redhat.com>, "Evgheni Dereveanchin" < > edere...@redhat.com> > > Cc: "Yaniv Kaul" <yk...@redhat.com>, "devel" <devel@ovirt.org>, "infra" > < > in...@ovirt.org> > > Sent: Thursday, 29 September, 2016 8:08:45 AM > > Subject: Re: [ovirt-devel] [VDSM] All tests using directio fail on CI > > > > Evgheni, > > Can you try switching the current RAM drive with zram? > > > > On Wed, Sep 28, 2016 at 11:43 PM, Nir Soffer <nsof...@redhat.com> wrote: > > > > > On Wed, Sep 28, 2016 at 11:39 PM, Yaniv Kaul <yk...@redhat.com> wrote: > > > > On Sep 28, 2016 11:37 PM, "Nir Soffer" <nsof...@redhat.com> wrote: > > > >> > > > >> On Wed, Sep 28, 2016 at 11:20 PM, Nir Soffer <nsof...@redhat.com> > > > wrote: > > > >> > On Wed, Sep 28, 2016 at 10:31 PM, Barak Korren < > bkor...@redhat.com> > > > >> > wrote: > > > >> >> The CI setup did not change recently. > > > >> > > > > >> > Great > > > >> > > > > >> >> All standard-CI jobs run inside mock (chroot) which is stored on > top > > > >> >> of a regular FS, so they should not be affected by the slave OS > at > > > all > > > >> >> as far as FS settings go. > > > >> >> > > > >> >> But perhaps some slave-OS/mock-OS combination is acting > strangely, so > > > >> >> could you be more specific and point to particular job runs that > > > fail? > > > >> > > > > >> > This jobs failed, but it was deleted (I get 404 now): > > > >> > http://jenkins.ovirt.org/job/vdsm_master_check-patch-fc24- > > > x86_64/2530/ > > > >> > > > >> Oops, wrong build. > > > >> > > > >> This is the failing build: > > > >> > > > >> > > > >> http://jenkins.ovirt.org/job/vdsm_master_check-patch-el7- > > > x86_64/1054/console > > > >> > > > >> And this is probably the reason - using a ram disk: > > > >> > > > >> 12:24:53 Building remotely on ovirt-srv08.phx.ovirt.org (phx > physical > > > >> integ-tests ram_disk fc23) in workspace > > > >> /home/jenkins/workspace/vdsm_master_check-patch-el7-x86_64 > > > >> > > > >> We cannot run the storage tests using a ramdisk. We are creating > > > >> (tiny) volumes and storage domains and doing copies, this code > cannot > > > >> work with ramdisk. > > > > > > > > Will it work on zram? > > > > What if we configure ram based iSCSI targets? > > > > > > I don't know, but it is easy to test - it this works the tests will > work: > > > > > > dd if=/dev/zero of=file bs=512 count=1 oflag=direct > > > _______________________________________________ > > > Infra mailing list > > > in...@ovirt.org > > > http://lists.ovirt.org/mailman/listinfo/infra > > > > > > > > > > > > > > > -- > > Eyal Edri > > Associate Manager > > RHV DevOps > > EMEA ENG Virtualization R&D > > Red Hat Israel > > > > phone: +972-9-7692018 > > irc: eedri (on #tlv #rhev-dev #rhev-integ) >
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