Re: [dpdk-users] AVX-512

[Don maillist <dlw.mailist@gmail.com>]

Be careful with AVX-512. It is best to use AVX-256 on Skylake. The AVX-512
applications do not run efficiently today on Skylake. It increases power
consumption in the underlying cores.

Best Regards,
Don

On Thu, Mar 1, 2018 at 7:57 PM, Tharaneedharan Vilwanathan <
vdharani@gmail.com> wrote:

> Hi Stephen,
>
> Appreciate your response.
>
> I have ESXi. I am still trying to map the KVM config with ESXi but no luck
> yet. I have requested the admin to figure out. If anyone is familiar with
> ESXi configuration for this, please let me know.
>
> Thanks
> dharani
>
> On Fri, Feb 23, 2018 at 11:38 AM, Stephen Hemminger <
> stephen@networkplumber.org> wrote:
>
> > On Fri, 23 Feb 2018 11:16:14 -0800
> > Tharaneedharan Vilwanathan <vdharani@gmail.com> wrote:
> >
> > > Hi All,
> > >
> > > I have a quick question. I got a new server with the CPU that should
> have
> > > AVX-512 support but I don't see it in Linux (Ubuntu 18.04).
> > >
> > > Here is the output:
> > >
> > > auto@auto-virtual-machine:~$ *cat /proc/cpuinfo*
> > > processor : 0
> > > vendor_id : GenuineIntel
> > > cpu family : 6
> > > model : 85
> > > model name : *Intel(R) Xeon(R) Gold 6130 CPU @ 2.10GHz*
> > > stepping : 4
> > > microcode : 0x2000029
> > > cpu MHz : 2095.078
> > > cache size : 22528 KB
> > > physical id : 0
> > > siblings : 2
> > > core id : 0
> > > cpu cores : 2
> > > apicid : 0
> > > initial apicid : 0
> > > fpu : yes
> > > fpu_exception : yes
> > > cpuid level : 22
> > > wp : yes
> > > flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
> pat
> > > pse36 clflush dts mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm
> > > constant_tsc arch_perfmon pebs bts nopl xtopology tsc_reliable
> > nonstop_tsc
> > > cpuid pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe
> popcnt
> > > tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm
> > > 3dnowprefetch cpuid_fault invpcid_single pti fsgsbase tsc_adjust bmi1
> hle
> > > avx2 smep bmi2 invpcid rtm rdseed adx smap xsaveopt arat
> > > bugs : cpu_meltdown spectre_v1 spectre_v2
> > > bogomips : 4190.15
> > > clflush size : 64
> > > cache_alignment : 64
> > > address sizes : 42 bits physical, 48 bits virtual
> > > power management:
> > >
> > > Can someone tell me why I don't see AVX-512?
> > >
> > > Appreciate your help.
> > >
> > > Thanks
> > > dharani
> >
> > If you are running in a VM, make sure that your hypervisor passes the avx
> > flags through.
> > In KVM this is usually done with the "Copy host CPU configuration" in
> virt
> > manager.
> >
>