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@xxxxxxxxxxx> 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@xxxxxxxxxx
<centos-virt-bounces@xxxxxxxxxx> on behalf of Laurentiu Soica
<laurentiu@xxxxxxxx>
SENT: Wednesday, August 17, 2016 6:38 AM
TO: Discussion about the virtualization on CentOS
SUBJECT: Re: 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@xxxxxxxxxx
<centos-virt-bounces@xxxxxxxxxx> on behalf of Laurentiu Soica
SENT: Wednesday, August 17, 2016 4:56 AM
TO: Discussion about the virtualization on CentOS
SUBJECT: Re: 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@xxxxxxxxxx
<centos-virt-bounces@xxxxxxxxxx> on behalf of Laurentiu Soica
SENT: Tuesday, August 16, 2016 7:16 AM
TO: Discussion about the virtualization on CentOS
SUBJECT: Re: Nested KVM issue
Yes. It is on both baremetal and compute node.
_______________________________________________
CentOS-virt mailing list
CentOS-virt@xxxxxxxxxx
https://lists.centos.org/mailman/listinfo/centos-virt
_______________________________________________
CentOS-virt mailing list
CentOS-virt@xxxxxxxxxx
https://lists.centos.org/mailman/listinfo/centos-virt
--
Laurentiu Soica
_______________________________________________
CentOS-virt mailing list
CentOS-virt@xxxxxxxxxx
https://lists.centos.org/mailman/listinfo/centos-virt
_______________________________________________
CentOS-virt mailing list
CentOS-virt@xxxxxxxxxx
https://lists.centos.org/mailman/listinfo/centos-virt
