multiple vcpus in hvm domu?

[david l goodrich]

despite a HVM domU with the following line
vcpus = 2
the OS only sees 1 CPU. is this intended? is there another
config directive I should use since it's HVM?

Thanks.
--david

[david l goodrich]

i'm running xen 4.1.6.1, i wonder if something got added in 4.2?

that's the right directive.
I checked a few of my systems. It seems to work fine on my sles12 and solaris 10 domU's
with netbsd 6.1.x and xen 4.2.x { x ??? 3 }. I haven't done an extensive check of my older systems.

x46-64-sles12:~ # more /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 45
stepping : 7
microcode : 0x70a
cpu MHz : 3300.176
cache size : 15360 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep
mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx
rdtscp lm constant_tsc arch_pe rfmon rep_good nopl eagerfpu pni
pclmulqdq ssse3 cx16 pcid sse4_1 sse4_2 x2apic popcnt
tsc_deadline_timer aes xsave avx hypervisor lahf_lm xsaveopt
bogomips : 6600.35 clflush size : 64
cache_alignment : 64
address sizes : 46 bits physical, 48 bits virtual
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 45
stepping : 7

...
HW
On Wed, 23 Apr 2014 15:15:21 -0500

despite a HVM domU with the following line
vcpus = 2
the OS only sees 1 CPU. is this intended? is there another
config directive I should use since it's HVM?
Thanks.
--david

...

[Manuel Bouyer]

Post by david l goodrich
i'm running xen 4.1.6.1, i wonder if something got added in 4.2?

It's also running fine for me with 4.1.x (if I remember properly, I started
using SMP HVM domUs with Xen 3.3). What OS is running in your domU ?

[david l goodrich]

OpenBSD and Windows XP. An off-list conversation reminded me
that some OSes require MP-capable kernels. Switching OpenBSD to
boot from bsd.mp shows two CPUs in the dmesg before it core
dumps, which isn't Xen's problem. Windows XP continues to show
only one cpu in performance manager, but shows two processors in
device manager. I don't know why there's only one processor in
perf manager, but I seem to be mistaken and xen seems to be doing
the right thing.

sorry about the noise.

Post by Manuel Bouyer

Post by david l goodrich
i'm running xen 4.1.6.1, i wonder if something got added in 4.2?

It's also running fine for me with 4.1.x (if I remember properly, I started
using SMP HVM domUs with Xen 3.3). What OS is running in your domU ?
--
NetBSD: 26 ans d'experience feront toujours la difference
--

[Manuel Bouyer]

Post by david l goodrich
OpenBSD and Windows XP. An off-list conversation reminded me
that some OSes require MP-capable kernels. Switching OpenBSD to
boot from bsd.mp shows two CPUs in the dmesg before it core
dumps, which isn't Xen's problem. Windows XP continues to show
only one cpu in performance manager, but shows two processors in
device manager. I don't know why there's only one processor in
perf manager, but I seem to be mistaken and xen seems to be doing
the right thing.

windows (at last up to XP/2003, I didn't test newer versions) detects the
hardware UP/SMP capabilities at install time, and can't be changed after
without a reinstall. So if you installed XP on a UP system, it won't be able
to use more than one CPU after.

[Tiago Ribeiro]

Post by Manuel Bouyer

Post by david l goodrich
OpenBSD and Windows XP. An off-list conversation reminded me
that some OSes require MP-capable kernels. Switching OpenBSD to
boot from bsd.mp shows two CPUs in the dmesg before it core
dumps, which isn't Xen's problem. Windows XP continues to show
only one cpu in performance manager, but shows two processors in
device manager. I don't know why there's only one processor in
perf manager, but I seem to be mistaken and xen seems to be doing
the right thing.

windows (at last up to XP/2003, I didn't test newer versions) detects the
hardware UP/SMP capabilities at install time, and can't be changed after
without a reinstall. So if you installed XP on a UP system, it won't be able
to use more than one CPU after.
--
NetBSD: 26 ans d'experience feront toujours la difference
--

...

When your vm is running if you execute

# xm vcpu-list

what the result?

In this case, my win2k8 have 3 vcpus (it’s a linux dom0, but on netbsd have same case).

xm vcpu-list
Name ID VCPU CPU State Time(s) CPU Affinity
Domain-0 0 0 0 r-- 37881.0 0
win2k8 23 0 3 r-- 393.7 any cpu
win2k8 23 1 2 -b- 276.2 any cpu
win2k8 23 2 1 -b- 227.2 any cpu


--
www.bsdjf.com.br

[Harry Waddell]

that's the right directive.

I checked a few of my systems. It seems to work fine on my sles12 and solaris 10 domU's
with netbsd 6.1.x and xen 4.2.x { x ≥ 3 }. I haven't done an extensive check of my older systems.

x46-64-sles12:~ # more /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 45
stepping : 7
microcode : 0x70a
cpu MHz : 3300.176
cache size : 15360 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep
mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx
rdtscp lm constant_tsc arch_pe rfmon rep_good nopl eagerfpu pni
pclmulqdq ssse3 cx16 pcid sse4_1 sse4_2 x2apic popcnt
tsc_deadline_timer aes xsave avx hypervisor lahf_lm xsaveopt
bogomips : 6600.35 clflush size : 64
cache_alignment : 64
address sizes : 46 bits physical, 48 bits virtual
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 45
stepping : 7

...

...


HW


On Wed, 23 Apr 2014 15:15:21 -0500

despite a HVM domU with the following line
vcpus = 2
the OS only sees 1 CPU. is this intended? is there another
config directive I should use since it's HVM?
Thanks.
--david