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Processing of data in SSE/AVX/AVX2

Hello!

Im working on my project and Im looking for the answer:

When Im processing 256-bits of data, is better to use (in one core) for this one whole YMMx register or to split them for 2x128-bits and process them through 2 XMMx registers at different ports, hence on different SSE/AVX unit (in Sandy Bridge there are 3 ports per core for AVX)?  Which option is faster?

Xeon Phi Coprocessor and Citrix XenServer 6.2

I am trying to use the Intel Xeon Phi Coprocessor card with a Citrix XenServer 6.2 guest VM (HVM guest) with PCI passthrough.

The following is my setup:

SuperMicro SYS-6037R-72RTF+
Dom0: XenServer release 6.2.0-70446c (xenenterprise) (Kernel 2.6.32.43-0.4.1.xs1.8.0.835.170778xen)
HVM Guest: CentOS 6.5 with stock kernel, Xeon Phi is passed through with the Xen pciback driver.

proc_bind

I specify for example my env variables as follows: "mic_kmp_place_threads=Xc,1t", "mic_omp_num_threads=X", "mic_kmp_affinity=scatter". I keep X smaller than available cores on mic.

1) Would there be any difference if I set my "mic_omp_proc_bind" to spread or close?

2) Also are there any documentation on "mic_omp_proc_bind"?

mpss 3.4 - No Mic cards found or specified on command line

I bet this is most common issue. We have installed the Card and the MPSS software. We are getting this message.

# micctrl --initdefaults
[Warning] No Mic cards found or specified on command line

We are able to detect the module:

# find /lib/modules -name mic.ko
/lib/modules/3.10.0-123.el7.x86_64/extra/mic.ko

OS sees the card:

 lspci | grep coprocessor

04:00.0 Co-processor: Intel Corporation Xeon Phi coprocessor SE10/7120 series (rev 11)

And here are other details:

using version 2015 of the compiler to build for mic does not seem to work on RHEL 6

I am trying to compile for both MIC and the host, and am hitting this error: x86_64-k1om-linux-ld: /lib64/libc.so.6: version `GLIBC_2.14' not found (required by x86_64-k1om-linux-ld) x86_64-k1om-linux-ld: /lib64/libc.so.6: version `GLIBC_2.14' not found (required by /opt/mpss/3.4/sysroots/x86_64-mpsssdk-linux/usr/lib/k1om-mpss-linux/../libz.so.1) GLIBC on RHEL 6 is 2.12.x.

Compiler version and offloading errors

while playing with the offloading examples found on this forum I ran into a little snag:

host A: Scientific Linux 6.5, Intel compiler v14, Xeon Phi 7100, mpss 3.3.2 stack

host B: CentOS 6.5, Intel compiler v15, 2 x Xeon Phi 5100, mpss 3.3.2 stack

When I compile an offload example on host A, then copy it over to host B and I try to run it I get:

[hostB] $ ./offload1.icc14
offload error: target executable is not available

It does not work even if I copy over the offload libraries from icc v14 to the new environment:

Compiler version and offloading errors

while playing with the offloading examples found on this forum I ran into a little snag:

host A: Scientific Linux 6.5, Intel compiler v14, Xeon Phi 7100, mpss 3.3.2 stack

host B: CentOS 6.5, Intel compiler v15, 2 x Xeon Phi 5100, mpss 3.3.2 stack

When I compile an offload example on host A, then copy it over to host B and I try to run it I get:

[hostB] $ ./offload1.icc14 
offload error: target executable is not available

It does not work even if I copy over the offload libraries from icc v14 to the new environment:

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