Re: [ovirt-users] High CPU Usage caused by migration thread on Node
Hi all, I think I found the solution on yesterday. The host which causes the CPU problems is in a cluster where the KSM option is activate. Someone here must have check it. I disable KSM on the cluster, disable NUMA and CPU pass through in the vm parameters, and no more high CPU usage by migration thread. Hope this solution can help someone else ! Styve Réponse ou transfert de la part de Styve JAUMOTTE De : Doron Fediuck [mailto:dfedi...@redhat.com] Envoyé : dimanche 25 septembre 2016 08:27 À : jaumotte, styve Cc : users@ovirt.org; Martin Sivák Objet : Re: [ovirt-users] High CPU Usage caused by migration thread on Node On Wed, Sep 21, 2016 at 12:28 PM, jaumotte, styve mailto:s.jaumo...@maine-et-loire.fr>> wrote: Hi, We’ve got a problem with a critical machine which running Oracle Database and if someone can help us it would be very nice. Our VM is running rhel 6.5 and is configuring with 16 cores (2 virtual socket with 8 virtual cores) and 240Gb. This virtual machine is running perfectly on the first host R620 : two cpu E5-2695 v2 - 12 cores on each cpu - and 384Gb of memory. We wan’t to move this virtual machine on a new server, Transtec with two E5-2650 v3 – 10 cores on each cpu – and 256Gb of memory. We have encountered high cpu usage on this host. Both servers are running centOS 7.2 and ovirt 3.6. We have already identified that on the node, many « migrate/N » are causing high cpu usage. We have tried few options : - Pass-Through Host CPU - Configure NUMA : numa node count = 2, numa pinning The first day the machine was running, everything is ok and migrate threads disapeared, but on the second day, high cpu and migration thread were back. Oracle services are being restarted everyday for cold backup but not the virtual machines. I don’t know if looking in the Numa options is a good idea and I don’t why the everything is running ok on the R620 (perhaps the available memory) Thank you for your advices. Styve ___ Users mailing list Users@ovirt.org<mailto:Users@ovirt.org> http://lists.ovirt.org/mailman/listinfo/users Hi Styve, Pass-Through Host CPU is irrelevant unless you have a specific CPU flag you need to utilize. So I suggest you refrain from using it. As for NUMA, it works well as long as it's not interleaving. Here as well you should use it only if you understand how it should be used. Otherwise the safe option for you is vCPU pinning. Can you please check your logs to see who is creating these threads and share it? ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Re: [ovirt-users] High CPU Usage caused by migration thread on Node
Hi, Thank you for your reply, I will disable at next reboot Numa options and cpu pass-through, and I will try vCPU pinning. You told me to check logs to see what is the origin of migration threads, could you please help me and give me more details in the ways to investigate. I begin to work with the perf command line but it is a little bit unclear. Styve Réponse ou transfert de la part de Styve JAUMOTTE De : Doron Fediuck [mailto:dfedi...@redhat.com] Envoyé : dimanche 25 septembre 2016 08:27 À : jaumotte, styve Cc : users@ovirt.org; Martin Sivák Objet : Re: [ovirt-users] High CPU Usage caused by migration thread on Node On Wed, Sep 21, 2016 at 12:28 PM, jaumotte, styve mailto:s.jaumo...@maine-et-loire.fr>> wrote: Hi, We’ve got a problem with a critical machine which running Oracle Database and if someone can help us it would be very nice. Our VM is running rhel 6.5 and is configuring with 16 cores (2 virtual socket with 8 virtual cores) and 240Gb. This virtual machine is running perfectly on the first host R620 : two cpu E5-2695 v2 - 12 cores on each cpu - and 384Gb of memory. We wan’t to move this virtual machine on a new server, Transtec with two E5-2650 v3 – 10 cores on each cpu – and 256Gb of memory. We have encountered high cpu usage on this host. Both servers are running centOS 7.2 and ovirt 3.6. We have already identified that on the node, many « migrate/N » are causing high cpu usage. We have tried few options : - Pass-Through Host CPU - Configure NUMA : numa node count = 2, numa pinning The first day the machine was running, everything is ok and migrate threads disapeared, but on the second day, high cpu and migration thread were back. Oracle services are being restarted everyday for cold backup but not the virtual machines. I don’t know if looking in the Numa options is a good idea and I don’t why the everything is running ok on the R620 (perhaps the available memory) Thank you for your advices. Styve ___ Users mailing list Users@ovirt.org<mailto:Users@ovirt.org> http://lists.ovirt.org/mailman/listinfo/users Hi Styve, Pass-Through Host CPU is irrelevant unless you have a specific CPU flag you need to utilize. So I suggest you refrain from using it. As for NUMA, it works well as long as it's not interleaving. Here as well you should use it only if you understand how it should be used. Otherwise the safe option for you is vCPU pinning. Can you please check your logs to see who is creating these threads and share it? ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Re: [ovirt-users] High CPU Usage caused by migration thread on Node
On Wed, Sep 21, 2016 at 12:28 PM, jaumotte, styve < s.jaumo...@maine-et-loire.fr> wrote: > Hi, > > > > We’ve got a problem with a critical machine which running Oracle Database > and if someone can help us it would be very nice. > > > > Our VM is running rhel 6.5 and is configuring with 16 cores (2 virtual > socket with 8 virtual cores) and 240Gb. > > > > This virtual machine is running perfectly on the first host R620 : two cpu > E5-2695 v2 - 12 cores on each cpu - and 384Gb of memory. > > > > We wan’t to move this virtual machine on a new server, Transtec with two > E5-2650 v3 – 10 cores on each cpu – and 256Gb of memory. We have > encountered high cpu usage on this host. > > > > Both servers are running centOS 7.2 and ovirt 3.6. We have already > identified that on the node, many « migrate/N » are causing high cpu usage. > > > > We have tried few options : > > - Pass-Through Host CPU > > - Configure NUMA : numa node count = 2, numa pinning > > The first day the machine was running, everything is ok and migrate > threads disapeared, but on the second day, high cpu and migration thread > were back. Oracle services are being restarted everyday for cold backup but > not the virtual machines. > > > > I don’t know if looking in the Numa options is a good idea and I don’t why > the everything is running ok on the R620 (perhaps the available memory) > > > > Thank you for your advices. > > > > Styve > > > > > > ___ > Users mailing list > Users@ovirt.org > http://lists.ovirt.org/mailman/listinfo/users > > Hi Styve, Pass-Through Host CPU is irrelevant unless you have a specific CPU flag you need to utilize. So I suggest you refrain from using it. As for NUMA, it works well as long as it's not interleaving. Here as well you should use it only if you understand how it should be used. Otherwise the safe option for you is vCPU pinning. Can you please check your logs to see who is creating these threads and share it? ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
[ovirt-users] High CPU Usage caused by migration thread on Node
Hi, We've got a problem with a critical machine which running Oracle Database and if someone can help us it would be very nice. Our VM is running rhel 6.5 and is configuring with 16 cores (2 virtual socket with 8 virtual cores) and 240Gb. This virtual machine is running perfectly on the first host R620 : two cpu E5-2695 v2 - 12 cores on each cpu - and 384Gb of memory. We wan't to move this virtual machine on a new server, Transtec with two E5-2650 v3 - 10 cores on each cpu - and 256Gb of memory. We have encountered high cpu usage on this host. Both servers are running centOS 7.2 and ovirt 3.6. We have already identified that on the node, many < migrate/N > are causing high cpu usage. We have tried few options : - Pass-Through Host CPU - Configure NUMA : numa node count = 2, numa pinning The first day the machine was running, everything is ok and migrate threads disapeared, but on the second day, high cpu and migration thread were back. Oracle services are being restarted everyday for cold backup but not the virtual machines. I don't know if looking in the Numa options is a good idea and I don't why the everything is running ok on the R620 (perhaps the available memory) Thank you for your advices. Styve ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
