Reindl Harald wrote:
Am 29.06.2013 23:12, schrieb Bill Davidsen:
> And right again. Unfortunately I didn't say or mean vSphere, but rather KVM, the
facility used by qemu-kvm to run
> virtual machines.
>
> Hardware CPU:
> vendor_id : GenuineIntel
> model name : Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz
> flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat pse36 clflush dts acpi mmx
> fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts
rep_good nopl xtopology
> nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2
ssse3 cx16 xtpr pdcm pcid
> sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb
xsaveopt pln pts dtherm
> tpr_shadow vnmi flexpriority ept vpid
>
> On 2.6.32-358.11.1.el6.i68 VM:
> vendor_id : GenuineIntel
> model name : QEMU Virtual CPU version 1.0.1
> flags : fpu de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pse36
clflush mmx fxsr sse sse2 syscall
> nx lm unfair_spinlock pni cx16 popcnt hypervisor lahf_lm
>
> But on 3.9.6-200.fc18.x86_64 VM:
> vendor_id : GenuineIntel
> model name : QEMU Virtual CPU version 1.0.1
> flags : fpu de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pse36
clflush mmx fxsr sse sse2
> syscall nx lm rep_good nopl pni cx16 popcnt hypervisor lahf_lm
>
> Other than the flag name change, neither VM has aes set, I assume the flag is blocked
for security, although I
> don't see bugs about it.
>
> Anyway, switching all our servers to something else at this time is not even a worth
discussion, so my note was
> just a warning for people using the KVM tools included in Fedora
looks like KVM is still far behind VMware
"model name: QEMU Virtual CPU version 1.0.1"
what the hell - on VMware you have the same CPU as the host and only "VMware
EVC"
is filtering CPU capabilities to provide relieable hot-migration between hosts
by make only the flags of the oldest CPU in the cluster visible to guests
That's why we use KVM, migrations may not be within a cluster. Or be real time
"migrations" as you are thinking of it, but rather may involve being backed up
until the next time there is a support need for the machine. Different
environment, different goals.
that's why a VMwar eguest has around 905-98 % of the native
performance because
there is only few binary translation and most instrcutions are passed 1:1
And as I remember if there was one old machine in the cluster you wouldn't have
the aes instruction either. That's from docs, haven't tried VMware in a very
long time.
--
Bill Davidsen <davidsen(a)tmr.com>
"'Nothing to hide' does not imply 'nothing to fear'"
- me
"AT&T could not seriously contend that a reasonable entity in its position
could have believed that the alleged domestic dragnet was legal."
-judge Vaughn R. Walker of the U.S. District Court
for the Northern District of California, EFF vs. AT&T