Virtualization limits for Red Hat Enterprise Linux with KVM

Updated -

The following limits apply to Red Hat Enterprise Linux Server with KVM virtualization.

For tested limits of OpenShift Virtualization, see the Supported Limits for OpenShift Virtualization 4.x article.

To see the limits for the former Red Hat Virtualization product, see Supported limits for Red Hat Virtualization.

Intel 64 and AMD64:

  Red Hat Enterprise Linux 7 Server with KVM Red Hat Enterprise Linux 8 Server with KVM Red Hat Enterprise Linux 9 Server with KVM Red Hat Enterprise Linux 10 Server with KVM
Maximum number of virtual CPUs in virtualized guest 240 710 40966 4096
Maximum memory in virtualized guest 6 TB2 16 TB1,2 16 TB1,2 64 TB1,2
Minimum memory in virtualized guest4 512 MB 512 MB 512 MB 1 GB

64-bit ARM:

  Red Hat Enterprise Linux 9 Server with KVM Red Hat Enterprise Linux 10 Server with KVM
Maximum number of virtual CPUs in virtualized guest 384 384
Maximum memory in virtualized guest 1 TB 1 TB
Minimum memory in virtualized guest4 1.5 GB 1.5 GB

IBM Z:

  Red Hat Enterprise Linux 8 Server with KVM Red Hat Enterprise Linux 9 Server with KVM Red Hat Enterprise Linux 10 Server with KVM
Maximum number of virtual CPUs in virtualized guest 2483 2483 2483
Maximum memory in virtualized guest 10 TB2 10 TB2 10 TB2
Minimum memory in virtualized guest4 1.5 GB (2 GB SE)5 1.5 GB (2 GB SE)5 1.5 GB (2 GB SE)5

IBM POWER 8 and POWER 9:

  Red Hat Enterprise Linux 7 Server with KVM Red Hat Enterprise Linux 8 Server with KVM Red Hat Enterprise Linux 9 Server with KVM Red Hat Enterprise Linux 10 Server with KVM
Maximum number of virtual CPUs in virtualized guest 192 384 Unsupported Unsupported
Maximum memory in virtualized guest 10 TB2 10 TB2 Unsupported Unsupported
Minimum memory in virtualized guest7 2 GB 2 GB Unsupported Unsupported

Other support considerations:

  • Supported limits reflect the current state of system testing by Red Hat and its partners. Systems exceeding these supported limits may be included in the Hardware Catalog after joint testing between Red Hat and its partners. If they exceed the supported limits posted here, entries in the Hardware Catalog will be fully supported.
  • In addition to supported limits reflecting hardware capability, there may be additional limits under the Red Hat Enterprise Linux subscription terms. Supported limits are subject to change based on ongoing testing activities.
  • For limits using the Xen hypervisor included with Red Hat Enterprise Linux 5, see Virtualization limits for Red Hat Enterprise Linux with Xen
  • Until 2021 there was a support limit of 4 active guests per RHEL hypervisor. This limit has been removed so more than 4 guests are supported.

Footnotes:

  1. Note that virtualized guests larger than 8 TB currently require explicit virtual NUMA configuration, because the maximum virtual NUMA node size is 8 TB.
  2. Live migrating guests with more than 1 TB of memory may have certain limitations. For details see the RHEL 8 or RHEL 9 documentation, based on your version of RHEL.
  3. If the VM is running in secure execution mode, the vCPU limit on IBM Z is only 247.
  4. VMs with only the minimum required memory are not suitable for running a more extensive configuration, such as a high number of virtual CPUs or devices.
  5. If the VM is running in secure execution mode, it requires more RAM to function correctly.
  6. RHEL 9.5 and earlier supports up to 710 virtualized CPUs. RHEL 9.6 and later supports up to 4096 virtualized CPUs.
  • Component
  • kvm

Comments