Laurentiu, Just to chip in, without thoroughly checking the thread (which I'd like to apologize in advance for): have you tried to test other kernel instead of the stock one? You can have a look at http://elrepo.org/tiki/kernel-ml and http://elrepo.org/tiki/kernel-lt and use them for some comparison testing. Cheers, --- Adi Pircalabu On 22-08-2016 18:31, Laurentiu Soica wrote: > No luck with qemu-kvm-ev, the behavior is the same. Running perf > record -a -g on the baremetal shows that most of the CPU time is in > _raw_spin_lock > > Children Self Command Shared Object > Symbol > - 93.62% > 93.62% qemu-kvm [kernel.kallsyms] [k] > _raw_spin_lock > > > - _raw_spin_lock > > > + 45.30% kvm_mmu_sync_roots > > > + 28.49% kvm_mmu_load > > > + 25.00% mmu_free_roots > > > + 1.12% tdp_page_fault > > În joi, 18 aug. 2016 la 11:59, Laurentiu Soica a > scris: > >> I've tried with KSM disabled and nothing changed. >> >> I've upgraded KVM to qemu-kvm-ev. I'm waiting to see if there are >> any improvements and report back. >> >> În mie., 17 aug. 2016 la 15:10, Boris Derzhavets >> <bderzhavets at hotmail.com> a scris: >> >> For myself KSM is unpredictable feature. The problem is Compute, >> just this node >> >> does "copy on write" , so only Compute. >> >> My concern exactly is where would it lead to worse or better Guest >> behavior ? >> >> I am not expecting complete fix. I would track via top/htop and >> dmesg via Cron on 1-2 hr >> >> period. >> >> ------------------------- >> >> FROM: centos-virt-bounces at centos.org >> <centos-virt-bounces at centos.org> on behalf of Laurentiu Soica >> <laurentiu at soica.ro> >> >> SENT: Wednesday, August 17, 2016 6:38 AM >> >> TO: Discussion about the virtualization on CentOS >> SUBJECT: Re: [CentOS-virt] Nested KVM issue >> >> Both baremetal and compute ? Are there any other metrics do you >> consider useful to collect for troubleshooting purposes ? >> >> În mie., 17 aug. 2016 la 13:04, Boris Derzhavets >> a scris: >> >> It sounds weird, but attempt to disable KSM and see would it help or >> no ? >> >> ------------------------- >> >> FROM: centos-virt-bounces at centos.org >> <centos-virt-bounces at centos.org> on behalf of Laurentiu Soica >> >> SENT: Wednesday, August 17, 2016 4:56 AM >> >> TO: Discussion about the virtualization on CentOS >> SUBJECT: Re: [CentOS-virt] Nested KVM issue >> >> Enabled the logging on both compute and baremetal. Nothing strange >> in logs: >> >> on baremetal : >> >> Wed Aug 17 11:51:01 EEST 2016: committed 62310764 free 58501808 >> Wed Aug 17 11:51:01 EEST 2016: 87025667 < 123574516 and free > >> 24714903, stop ksm >> >> on compute: >> >> Wed Aug 17 08:52:52 UTC 2016: committed 24547132 free 76730936 >> Wed Aug 17 08:52:52 UTC 2016: 45139624 < 102962460 and free > >> 20592492, stop ksm >> >> and the compute node is again at 100% CPU utilization. >> >> În mar., 16 aug. 2016 la 15:26, Boris Derzhavets >> a scris: >> >> I would enable ksmtuned logging ,if it has been done verify logs >> >> ------------------------- >> >> FROM: centos-virt-bounces at centos.org >> <centos-virt-bounces at centos.org> on behalf of Laurentiu Soica >> >> SENT: Tuesday, August 16, 2016 7:16 AM >> >> TO: Discussion about the virtualization on CentOS >> SUBJECT: Re: [CentOS-virt] Nested KVM issue >> >> Yes. It is on both baremetal and compute node. >> >> _______________________________________________ >> CentOS-virt mailing list >> CentOS-virt at centos.org >> https://lists.centos.org/mailman/listinfo/centos-virt > _______________________________________________ > CentOS-virt mailing list > CentOS-virt at centos.org > https://lists.centos.org/mailman/listinfo/centos-virt > > -- > > Laurentiu Soica > _______________________________________________ > CentOS-virt mailing list > CentOS-virt at centos.org > https://lists.centos.org/mailman/listinfo/centos-virt