3 Replies Latest reply on Mar 4, 2019 11:50 AM by nfaf1

    Enabling HugePages

    sgunelius Expert

      I've opened a support call with HP/VMware on this issue and while I'm waiting on their response, I thought I'd try the community.  We've recently started virtualizing some of our more demanding Oracle environments and our DBAs reported that the latest VM we deployed (Oracle Linux 6.4) doesn't have HugePages enabled.  I would think this setting would need to be done at the Guest rather than the Host, but am not entirely sure.  Thank you in advance for any insight you can offer.

       

      Scott

        • 1. Re: Enabling HugePages
          MKguy Virtuoso

          Please post the output of the following commands from the guest OS:

          # cat /proc/cpuinfo

          # cat /proc/meminfo

          # cat /sys/kernel/mm/transparent_hugepage/enabled

          # numactl --hardware

          # numactl --show

           

          Does the VM have more than 8 vCPUs? I'm not sure but I think large memory pages might require a NUMA topology on the guest OS. By default ESXi only presents a virtual NUMA topology to the guest if the VM is configured for more than 8 vCPUs.

          • 2. Re: Enabling HugePages
            SBALASUBRAMANIAN Novice
            vExpertVMware Employees

            Huge pages has nothing to do with NUMA, regardless of whether vNUMA is enabled (by default on vcpu > 8) or not, huge pages is a Guest OS thingy.

             

            nr.hugepages needs to be setup in /etc/sysct.conf along with use_large_page parameter in Oracle init/spfile

            Sudhir Balasubramanian
            Staff Solution Architect & Oracle Field Practice Lead (CPBU TMM)
            Oracle ACE & Oracle Groundbreaker Ambassador https://apex.oracle.com/pls/apex/f?p=19297:3
            VMware vExpert https://vexpert.vmware.com/directory/1038
            Member of the Office of the Chief Technical Ambassador VMware (Alumni)
            VMSIG Technology Advisor http://vmsig.org/about/
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            http://vracdba.com/ | https://blogs.vmware.com/apps/author/sudhirbalasubramanian/ https://community.oracle.com/blogs/sudhirb

            “Virtualizing Oracle Business Critical Databases on VMware SDDC” - A Comprehensive authority for Oracle DBA’s on the subject of Oracle & Linux on vSphere:
            https://www.amazon.com/Virtualize-Oracle-Business-Critical-Databases/dp/1500135127
            • 3. Re: Enabling HugePages
              nfaf1 Novice

              Hello,

               

              Sorry to hijack this thread but I have this exact problem.

               

              I am running ESXi 6.7 and I have enabled hugapages support as per Huge Pages

               

              but this still doesn't do anything

               

              cat /proc/meminfo | grep -i huge

              AnonHugePages:    329728 kB

              ShmemHugePages:        0 kB

              HugePages_Total:       4

              HugePages_Free:        4

              HugePages_Rsvd:        0

              HugePages_Surp:        0

              Hugepagesize:       2048 kB

               

              This should be to 1G

               

              The other parameters seem to go well:

               

              cat /proc/sys/vm/nr_hugepages

              4

               

              Can someone help ? as my container doesn't start because of this ....

               

               

              [  496.326645] hugetlbfs: Unsupported page size 1024 MB

              [  497.030697] hugetlbfs: Unsupported page size 1024 MB

              [  497.632851] hugetlbfs: Unsupported page size 1024 MB

              [  498.237018] hugetlbfs: Unsupported page size 1024 MB

              .....

               

              Thank you

               

              Nuno