I'm trying to run a code using MPI, but the number of CPUs reported to the code is always 1. I was originally trying to test on a system with Intel Core 2 Duo CPUs, but was told those CPUs were not supported. I was then told the Intel Xeon 5600 series CPUs were supported. We are almost ready to switch to that system, but we're now testing on a system with Intel Xeon Gold 6152 CPUs, and it doesn't work on those CPUs either. The system we need this to work on has Intel Xeon 5667 CPUs.
So my two questions are:
Will MPI work correctly on Intel Xeon 5667 CPUs? This is what we need MPI to work on. Also interested in Xeon 5675 CPus.
Will MPI work correctly on Intel Xeon Gold 6152 CPUs? If this is supposed to work, then we need to find out why it doesn't work.
As a bonus question, is there somewhere to find out what CPUs MPI does and does not work on? Like a list?
All supported processors you can find in the Release Notes, section "Hardware Requirements"
If you observe some issues on the supported processors, please send me a reproducer and full output.
Best Regards, Anatoliy
I've seen that, but I don't know what it means. I'm not an expert on processor families, what they include, or how they relate. For example, it says it supports "Intel® Core™ processor family or higher", but I was told Intel Core 2 Duo is NOT supported. Isn't Core 2 Duo part of the Core processor family? From the name I'd expect that it was. Plus, the very first thing it says is "Systems based on the Intel® 64 architecture". Core 2 Duo is certainly 64 bit.
Then it says it supports "Intel® Xeon® E5 v3 processor family" and "Intel® Xeon® E7 v2 processor family". Does E5 include the Xeon 5667 and the Xeon 5675, or are those a completely different series of processors? I have no idea, and I've been unable to find out. If they are in the E5 family, are those v3, or are they maybe only v2? And it says "recommended", so maybe v3 are the most recent processor, but v2 processors work? (not that I know what v3 and v2 mean).
I've tried looking this up, and there's a bazillion numbers and different processors. But I've never found any kind of decoder ring to tell me how the one set of numbers relates to another set of numbers. Maybe this is obvious for some people, but for me, I have no clue.
The best reference I have found to Intel processor numbering/naming is https://en.wikipedia.org/wiki/List_of_Intel_Xeon_microprocessors
You will need to figure out which version of MPI you are using to find the correct set of release notes.
The "Xeon 5667" and "Xeon 5675" processors are "Westmere-EP". On the Intel MPI library release notes page linked above, there is a section called "Removals" that includes important info: Intel MPI 2019 removes support for platforms older than Sandy Bridge. From the wikipedia page, you will see that the Nehalem/Westmere processors precede Sandy Bridge, so I would expect these processors to be unsupported for all Intel 2019 and newer MPI releases.
The "Xeon Gold 6152" processor is a "Skylake-SP". These are relatively new (2017), and are definitely supported by recent Intel MPI libraries. The Intel MPI release notes page mentions "Skylake" as a performance tuning target for MPI 2017 update 4, so the processor should be supported by Intel 2017, 2018, and 2019 MPI software.