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  • 1.  Monster VM gets corrupt disk

    Posted Oct 24, 2023 11:34 AM

    VMware ESXi, 7.0.3, 22348816

    larstr_0-1698147074694.png

     

    I have a nice little VM here with 3TB ram, 20TB storage and 160 vcpus. The problem is that once we assign more than 128 cpus the disk gets corrupted if we copy files into the system. With 128 cpus or less no such problems occur. 

    Guest OS is Ubuntu 22.04.3 LTS

     

    Anyone seen something like this before?

     

    Lars

     

     



  • 2.  RE: Monster VM gets corrupt disk

    Posted Oct 24, 2023 08:45 PM

    In my experience this is more related to the overcommit ratio, what is the underlying CPU logical core count? Is there anything else running on the host?



  • 3.  RE: Monster VM gets corrupt disk

    Posted Oct 24, 2023 10:37 PM

    You can't overcommit the number of cpus for a single VM on ESXi like you can on Power. Logical core count is 256 and nothing else is running on this host.

     

    Lars



  • 4.  RE: Monster VM gets corrupt disk

    Broadcom Employee
    Posted Oct 25, 2023 07:06 AM

    I would suggest filing a bug Lars, will do a search internally, but not seen this before.



  • 5.  RE: Monster VM gets corrupt disk

    Posted Oct 25, 2023 08:22 AM

    Thank you Duncan,

    We have opened SR with both VMware and Dell support. Since there seems to be little progress so far I'm also asking here, hoping that we're not the first ones to encounter this problem.

     

    Lars



  • 6.  RE: Monster VM gets corrupt disk

    Broadcom Employee
    Posted Oct 25, 2023 10:26 AM

    I cannot find anything useful internally so far to be honest. You may want to ask for the SR to be escalated.



  • 7.  RE: Monster VM gets corrupt disk

    Posted Oct 25, 2023 11:00 AM
    Can I just ask, is this VM running with a BIOS or EFI?


  • 8.  RE: Monster VM gets corrupt disk

    Posted Oct 31, 2023 09:53 AM

    CallistoJag,

    The maximum number of cores with BIOS seems to be 128:

    "[msg.vmx.invalidConfigForLargeVM] This virtual machine cannot be powered on because the current configuration does not support 160 CPUs. Decrease the virtual CPU count to 128 or enable EFI firmware and IOMMU support."

     

    ..so efi is our only option.

     

    Lars