AMD Epyc experience?



  • Does anyone have experience running VM hosts on AMD Epyc CPUs?

    Are there any gotchas or is it just smooth sailing?



  • @pete-s said in AMD Epyc experience?:

    Does anyone have experience running VM hosts on AMD Epyc CPUs?

    Are there any gotchas or is it just smooth sailing?

    I haven't had the opportunity yet. That said, why did this question even come up? It's not like the Opteron's that were the previous server CPUs had any issues, and this tech has just worked for something like 18 years in the x86 world. Something weird would be going on for someone to even put this question forward.



  • These are genuine AMD, not Intel clones, so really no expectation of problems given it's all AMD64 architecture.



  • @pete-s said in AMD Epyc experience?:

    Does anyone have experience running VM hosts on AMD Epyc CPUs?

    Are there any gotchas or is it just smooth sailing?

    I am using white box machien with Ryzen 7 1700 as server with KVM, to handle a couple of VMs for small company like nextcloud and stuff, it is what you expect from any other machine.

    I know this is not server part but I loved pairing it with an AMD 370x mobo with 8 port SATA allowing a nice software raid 10. I can pretend that it is EPYC, in my mind it is good setup.



  • @travisdh1 said in AMD Epyc experience?:

    @pete-s said in AMD Epyc experience?:

    Does anyone have experience running VM hosts on AMD Epyc CPUs?

    Are there any gotchas or is it just smooth sailing?

    I haven't had the opportunity yet. That said, why did this question even come up? It's not like the Opteron's that were the previous server CPUs had any issues, and this tech has just worked for something like 18 years in the x86 world. Something weird would be going on for someone to even put this question forward.

    Of course the CPUs will work but there might still be issues.

    Hardware problems are not likely but not unheard of - for instance Intel's C2000 series CPUs have premature death problem. Maybe more common would be software issues like for instance Intel X553 NIC drivers that sits inside the C3000 CPUs.

    With new CPUs you have new chipsets and whatnot that could cause problems until everything is sorted out. There could also be performance issues depending on kernel versions or patches. There could also be situations for certain workloads where maybe the Epyc surpasses or doesn't live up to expectations. That's the kind of things I was thinking about.



  • @pete-s said in AMD Epyc experience?:

    @travisdh1 said in AMD Epyc experience?:

    @pete-s said in AMD Epyc experience?:

    Does anyone have experience running VM hosts on AMD Epyc CPUs?

    Are there any gotchas or is it just smooth sailing?

    I haven't had the opportunity yet. That said, why did this question even come up? It's not like the Opteron's that were the previous server CPUs had any issues, and this tech has just worked for something like 18 years in the x86 world. Something weird would be going on for someone to even put this question forward.

    Of course the CPUs will work but there might still be issues.

    Hardware problems are not likely but not unheard of - for instance Intel's C2000 series CPUs have premature death problem. Maybe more common would be software issues like for instance Intel X553 NIC drivers that sits inside the C3000 CPUs.

    With new CPUs you have new chipsets and whatnot that could cause problems until everything is sorted out. There could also be performance issues depending on kernel versions or patches. There could also be situations for certain workloads where maybe the Epyc surpasses or doesn't live up to expectations. That's the kind of things I was thinking about.

    Then I'd expect a question about issues with the new CPU in general, not something specific to virtualization.

    I haven't heard about any issues with them yet. The price/performance of EPIC is just to good to pass up. Unless something is horrifically wrong, that's definitely the way I'd go if I have a choice in the matter.



  • @travisdh1 said in AMD Epyc experience?:

    I haven't heard about any issues with them yet. The price/performance of EPIC is just to good to pass up. Unless something is horrifically wrong, that's definitely the way I'd go if I have a choice in the matter.

    That's kind of what I'm thinking myself.


  • Vendor

    Couple thoughts...

    1. It's spelled EPYC...

    2. There were some weird NUMA considerations when trying to saturate 100Gbps Ethernet NIC's. I saw some firmware improvement/workarounds (basically stick TCP to a core so it wouldn't span NUMA nodes). 99% of people are not going to care about this, and the work around seems to be holding from what I've seen.

    3. For Single socket it's really the best bang for buck out there. I've seen some impressive vSAN numbers on it if anyone's wondering. It doesn't lock out 1/2 the PCI-E or Memory lanes like Intel in a single socket config.

    4. I've got a RYZEN at home, and quite happy with it.

    5. I'm hearing Intel made some optimizations for multi-threaded and cloud native workloads in Skylake that cause issues for .NET and single threaded apps. I haven't done any bake offs but I'm curious if AMD went down the same pass (especially with spin locks). If you have older .NET code with lots of spin locks you want to get it updated or get ready for potential (heavy) regressions on performance vs. Broadwell. We are entering a weird situation where CPU vendors are starting to NOT optimize for enterprise applications but for the mega clouds.

    6. While I think ARM is awesome, there also is a LOOOOOOOT of optimization to be done with compilers before it gets taken seriously outside of edge cases, or homogenous workloads where people will invest the time like CloudFlare.

    7. It requires a outage to migrate between Intel and AMD at a virtualization layer. Intel also has QuickAssit and some other interesting offload, as well as Apache Pass technology.