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SUSE Best Practices for SAP HANA on KVM

SUSE Linux Enterprise Server for SAP Applications 12 SP2

SUSE Best Practices

SAP

Authors
Matt Fleming, Senior Software Engineer (SUSE)
Lee Martin, SAP Architect & Technical Manager (SUSE)
Image
SUSE Linux Enterprise Server for SAP Applications 12 SP2

This best practice document describes how SUSE Linux Enterprise Server for SAP Applications 12 SP2 with KVM should be configured to run SAP HANA for use in production environments. Configurations which are not set up according to this best practice guide are considered as unsupported by SAP for production workloads.

While this document is not compulsory for non-production SAP HANA workloads, it may still be useful to help ensure optimal performance in such scenarios.

Disclaimer: Documents published as part of the SUSE Best Practices series have been contributed voluntarily by SUSE employees and third parties. They are meant to serve as examples of how particular actions can be performed. They have been compiled with utmost attention to detail. However, this does not guarantee complete accuracy. SUSE cannot verify that actions described in these documents do what is claimed or whether actions described have unintended consequences. SUSE LLC, its affiliates, the authors, and the translators may not be held liable for possible errors or the consequences thereof.

1 Introduction

  

This best practice document describes how SUSE Linux Enterprise Server for SAP Applications 12 SP2 with KVM should be configured to run SAP HANA for use in production environments. The setup of the SAP HANA system or other components like HA clusters are beyond the scope of this document.

The following sections describe how to set up and configure the three KVM components required to run SAP HANA on KVM:

Follow Section 2, “Supported Scenarios and Prerequisites” and the respective SAP Notes to ensure a supported configuration. Most of the configuration options are specific to the libvirt package and therefore require modifying the VM guest’s domain XML file.

1.1 Definitions

  

  • Hypervisor: The software running directly on the physical sever to create and run VMs (Virtual Machines).

  • Virtual Machine: is an emulation of a computer.

  • Guest OS: The Operating System running inside the VM (Virtual Machine). This is the OS running SAP HANA and therefore the one that should be checked for SAP HANA support as per SAP Note 2235581 “SAP HANA: Supported Operating Systems” (https://launchpad.support.sap.com/#/notes/2235581) and the “SAP HANA Hardware Directory” (https://www.sap.com/dmc/exp/2014-09-02-hana-hardware/enEN/appliances.html).

  • Paravirtualization: Allows direct communication between the Hypervisor and the VM Guest resulting in a lower overhead and better performance.

  • libvirt: A management interface for KVM.

  • qemu: The virtual machine emulator, also seen a process on the Hypervisor running the VM.

  • SI units: Some commands and configurations use the decimal prefix (for example GB), while other use the binary prefix (for example GiB). In this document we use the binary prefix where possible.

For a general overview of the technical components of the KVM architecture, refer to https://documentation.suse.com/sles/12-SP4/html/SLES-all/cha-kvm-intro.html

1.2 SAP HANA Virtualization Scenarios

  

SAP supports virtualization technologies for SAP HANA usage on a per scenario basis:

  • Single-VM - One VM per Hypervisor/physical server for SAP HANA Scale-Up (NOTE: SAP does not allow any other VM or workload on the same server)

  • Multi-VM - Multiple VM’s per Hypervisor/physical server for SAP HANA Scale-Up

  • Scale-Out - For SAP HANA Scale-Out

See SAP Notes:

2 Supported Scenarios and Prerequisites

  

Follow this SUSE Best Practices for SAP HANA on KVM - SUSE Linux Enterprise Server for SAP Applications 12 SP2 document which describes the steps necessary to create a supported SAP HANA on KVM configuration. SUSE Linux Enterprise Server for SAP Applications must be used for both Hypervisor and Guest.

Inquiries about scenarios not listed here should be directed to <>

2.1 Supported Scenarios

  

At the time of this publication the following configurations are supported for production use:

Table 1: Supported Combinations
  
CPU ArchitectureSAP HANA scale-up (single VM)SAP HANA scale-up (multi VM)SAP HANA Scale-Out

Haswell (Intel v3)

- Hypervisor: SLES for SAP 12 SP2 - Guest: SLES for SAP 12 SP1 onward - Size: max. 4 socket1, 2 TiB RAM

no

no

1 Maximum 4 sockets using Intel standard chipsets on a single system board, for example Lenovo* x3850, HPE*/SGI* UV300 etc.

Check the following SAP Notes for the latest details of supported SAP HANA on KVM scenarios.

2.2 Sizing

  

It is recommended to reserve the following resources for the Hypervisor:

  • 7% RAM

  • 1x Physical CPU core (2x Logical CPU/Hyperthreads) per Socket

2.2.1 Memory Sizing

  

Since SAP HANA runs inside the VM, it is the RAM size of the VM which must be used as the basis for SAP HANA Memory sizing.

2.2.2 CPU Sizing

  

In addition to the above mentioned CPU core reservation for the Hypervisor (see Section 4.3, “vCPU and vNUMA Topology” section for details), some artificial workload tests on Intel Haswell CPUs have shown an approximately 20% overhead when running SAP HANA on KVM. Therefore a thorough test of the configuration for the required workload is highly recommended before “go live”.

There are two main ways to deal with CPU sizing from a sizing perspective:

  1. Follow the fixed core-to-memory ratios for SAP HANA as defined by SAP:

    • The certification of the SAP HANA Appliance hardware to be used for KVM prescribes a fixed maximum amount of memory (RAM) which is allowed for each CPU core, also known as “core-to-memory ratio”. The specific ratio also depends on what workload the system will be used for, that is the Appliance Type: OLTP (Scale-up: SoH/S4H) or OLAP (Scale-up: BWoH/BW4H/DM/SoH/S4H).

    • The relevant core-to-memory ratio required to size a VM can be easily calculated as follows:

      • Go to the “SAP HANA Certified Hardware Directory” https://www.sap.com/dmc/exp/2014-09-02-hana-hardware/enEN/appliances.html.

      • Select the required SAP HANA Appliance and Appliance Type (for example Haswell for BWoH).

      • Look for the largest certified RAM size for the number of CPU Sockets on the server (for example 2048 GiB on 4-Socket).

      • Look up the number of cores per CPU of this CPU Architecture used in SAP HANA Appliances. The CPU model numbers are listed at: https://www.sap.com/dmc/exp/2014-09-02-hana-hardware/enEN/index.html#details (for example 18).

      • Using the above values calculate the total number of cores on the certified Appliance by multiplying number of sockets by number of cores (for example 4x18=72).

      • Now divide the Appliance RAM by the total number of cores (not hyperthreads) to give you the “core-to-memory” ratio. (for example 2048 GiB/72 = approx. 28 GiB per core).

    • Calculate the RAM size the VM needs to be compliant with the appropriate core-to-memory ratio defined by SAP:

      • Take the total number of CPU cores (not hyperthreads) on the Hypervisor and subtract one core per socket for the Hypervisor (for example 72-4=68).

      • Now take account of the Hypervisor overhead by multiplying the previous value by a factor of “1-overhead” (for example 1 - 0.20% = factor 0.8, so 68*0.8=55 effective cores).

      • Multiply the resulting number of CPU cores for the VM by the SAP HANA core-to-memory ratio to calculate to maximum VM RAM size limit by SAP for this amount of CPU power (for example 55 effective cores * 28 GiB per core = 1540 GiB Max VM RAM size for BWoH).

      • Now, calculate the maximum VM RAM size limit by SUSE by checking the Table 1, “Supported Combinations” table in this document for the maximum supported KVM Hypervisor RAM size for SAP HANA and then subtracting the 7% memory overhead (for example 2048 GiB * 0.93 (the 7% RAM overhead) = 1904 GiB Max VM RAM size).

    • Finally, the actual RAM size of the VM to be configured must not exceed the LOWEST of the two above calculated SAP and SUSE “Max VM RAM size” limits.

    • Conclusion:

      • Based on the example given above: From available CPU power in the VM, SAP would allow a maximum RAM size of up to 1540 GiB for a VM running OLAP/BWoH when following the predefined core-to-memory ratio.

      • Since OLTP/SoH has a much higher core-to-memory ratio (43 GiB/core) SAP would allow a maximum of 2611 GiB, which is well above the 1904 GiB limit for KVM in the example above.

    • See the table Table 2, “SAP HANA core-to-memory ratio examples” below for some current examples of SAP HANA core-to-memory ratios.

  2. Follow the SAP HANA TDI “Phase 5” rules as defined by SAP:

Table 2: SAP HANA core-to-memory ratio examples
  
CPU ArchitectureAppliance TypeMax Memory SizeSocketsCores per SocketSAP HANA core-to-memory ratio

Haswell (Intel v3)

OLTP

3072 GiB

4

18

43 GiB/core

Haswell (Intel v3)

OLAP

2048 GiB

4

18

28 GiB/core

2.3 KVM Hypervisor Version

  

The Hypervisor must be configured according to this “SUSE Best Practices for SAP HANA on KVM - SUSE Linux Enterprise Server for SAP Applications 12 SP2” guide and fulfill the following minimal requirements:

  • SUSE Linux Enterprise Server for SAP Applications 12 SP2 (“Unlimited Virtual Machines” subscription)

    • kernel (Only major version 4.4, minimum package version 4.4.49-92.11)

    • libvirt (Only major version 2.0, minimum package version 2.0.0-27.12.1)

    • qemu (Only major version 2.6, minimum package version 2.6.2-41.9.1)

2.4 Hypervisor Hardware

  

Use SAP HANA certified servers and storage as per SAP HANA Hardware Directory at: https://www.sap.com/dmc/exp/2014-09-02-hana-hardware/enEN/appliances.html

2.5 Guest VM

  

The guest VM must:

3 Hypervisor

  

3.1 KVM Hypervisor Installation

  

For details refer to Section 6.4 Installation of Virtualization Components of the SUSE Virtualization Guide (https://documentation.suse.com/sles/12-SP4/html/SLES-all/cha-vt-installation.html#sec-vt-installation-patterns)

Install the KVM packages using the following Zypper patterns:

zypper in -t pattern kvm_server kvm_tools

In addition, it is also useful to install the “lstopo” tool which is part of the “hwloc” package contained inside the “HPC Module” for SUSE Linux Enterprise Server.

3.2 Configure Networking on Hypervisor

  

To achieve maximum performance required for productive SAP HANA workloads the PCI address of the respective network port(s) must be assigned directly into the KVM Guest VM to ensure that the Guest VM has enough network device channels to accommodate the network traffic. Ideally the VM Guest should be able to access the same number of network device channels as the host, this can be checked and compared between host and guest VM with ethtool -l <device>, for example:

# ethtool -l eth1
Channel parameters for eth1:
Pre-set maximums:
RX:             0
TX:             0
Other:          1
Combined:       63
Current hardware settings:
RX:             0
TX:             0
Other:          1
Combined:       63

3.2.1 Assign Network Port at PCI NIC Level

  

The required network port(s) should be assigned to the Guest VM as described in section “14.10.2 Adding a PCI Device with virsh” in the SUSE Virtualization Guide for SUSE Linux Enterprise Server 12 SP2(https://documentation.suse.com/sles/12-SP2/)

Persist detach of PCI NIC port. Before starting the VM, the PCI NIC port must be detached from the Hypervisor OS, otherwise the VM will not start. The PCI NIC detach can be automated at boot time by creating a service file (after-local.service) pointing to /etc/init.d/after.local which contains the commands to detach the NIC.

Create the systemd unit file /etc/systemd/system/after.local.

[Unit]
Description=/etc/init.d/after.local Compatibility
After=libvirtd.service
Requires=libvirtd.service
[Service]
Type=oneshot
ExecStart=/etc/init.d/after.local
RemainAfterExit=true

[Install]
WantedBy=multi-user.target

Then create the script /etc/init.d/after.local which will detach the PCI device (where “pci_xxxx_xx_xx_0” must be replaced with the correct PCI address).

#! /bin/sh
#
# Copyright (c) 2010 SuSE LINUX Products GmbH, Germany.  All rights reserved.
# ...
virsh nodedev-detach pci_xxxx_xx_xx_0

3.3 Storage Configuration on Hypervisor

  

As with compute resources, the storage used for running SAP HANA must also be SAP certified. Therefore only the storage from SAP HANA Appliances or SAP HANA Certified Enterprise Storage (https://www.sap.com/dmc/exp/2014-09-02-hana-hardware/enEN/enterprise-storage.html) is supported. In all cases the SAP HANA storage configuration recommendations from the respective hardware vendor and the SAP HANA Storage Requirements for TDI (hhttps://www.sap.com/documents/2016/05/e8705aae-717c-0010-82c7-eda71af511fa.html) should be followed. The SUSE Best Practices for SAP HANA on KVM - SUSE Linux Enterprise Server for SAP Applications 12 SP2 has been designed and tested to map the block devices for SAP HANA on the Hypervisor directly into the VM. Therefore any LVM (Logical Volume Manager) configuration should be made inside the Guest VM only. Multipathing by contrast should be only configured on the Hypervisor.

Ultimately the storage for SAP HANA must be able to fulfill the SAP HANA HWCCT requirements from within the VM. For details on HWCCT and the required storage KPI’s refer to SAP Note 1943937 “Hardware Configuration Check Tool - Central Note” (https://launchpad.support.sap.com/notes/1943937) and SAP Note 2501817 - HWCCT 1.0 (≥220) (https://launchpad.support.sap.com/notes/2501817).

Network Attached Storage has not been tested with SAP HANA on KVM, if there is a requirement for this contact <>.

Most of the configuration steps to configure the storage are at the Guest VM XML level, see section Section 4.4, “Storage”. Nevertheless storage on the Hypervisor should:

  • Follow the storage layout recommendations from the appropriate hardware vendor.

  • Not use LVM (Logical Volume Manager) on the Hypervisor level for SAP HANA volumes since nested LVM is not supported.

  • Configure Multipathing on the Hypervisor only, not inside the Guest VM.

3.4 Hypervisor Operating System Configuration

  

3.4.1 tuned

  

Install “tuned” and set the profile to “latency-performance”. Do not use the “sap-hana profile” on the Hypervisor. This can be configured with the following commands:

zypper in tuned

systemctl enable tuned

systemctl start tuned

tuned-adm profile latency-performance
3.4.1.1 Verify “tuned” Has Set CPU Frequency Governor and Performance Bias
  

The CPU frequency governor should be set to “performance” to avoid latency issues because of ramping the CPU frequency up and down in response to changes in the system’s load. The governor setting can be verified with the following command to check what is set under “current policy”:

cpupower -c all  frequency-info

Additionally the performance bias setting should also be set to 0 (performance). The performance bias setting can be verified with the following command:

cpupower -c all info

3.4.2 irqbalance

  

The irqbalance service should be disabled because it can cause latency issues when the /proc/irq/* files are read. To disable irqbalance run the following command:

systemctl disable irqbalance.service

systemctl stop irqbalance.service

3.4.3 Customize the Linux Kernel Boot Options

  

To edit the boot options for the Linux kernel to the following:

  1. Edit /etc/defaults/grub and add the following boot options to the line “GRUB_CMDLINE_LINUX_DEFAULT” (A detailed explanation of these options follows).

    numa_balancing=disable   kvm_intel.ple_gap=0  transparent_hugepage=never  elevator=deadline  intel_idle.max_cstate=1  processor.max_cstate=1 default_hugepagesz=1GB hugepagesz=1GB hugepages=<number of hugepages>
    Note
    Note: Calculating Value

    The value for “<number of hugepages>” should be calculated by taking the number GiB’s of RAM minus approx. 7% for the Hypervisor OS. For example 2 TiB RAM (2048 GiB) minus 7% are approx. 1900 hugepages

  2. Run the following command:

    grub2-mkconfig -o /boot/grub2/grub.cfg

  3. Reboot the system:

    reboot

3.4.4 Technical Explanation of the Above Described Configuration Settings

  

Automatic NUMA Balancing (numa_balancing=disable)

Automatic NUMA balancing can result in increased system latency and should therefore be disabled.

KVM PLE-GAP (kvm_intel.ple_gap=0)

Pause Loop Exit (PLE) is a feature whereby a spinning guest CPU releases the physical CPU until a lock is free. This is useful in cases where multiple virtual CPUs are using the same physical CPU but causes unnecessary delays when a guest is not overcommitted.

Transparent Hugepages (transparent_hugepage=never)

Because 1G pages are used for the virtual machine, then there is no additional benefit from having THP enabled. Disabling it will avoid khugepaged interfering with the virtual machine while it scans for pages to promote to hugepages.

I/O Scheduler (elevator=deadline)

The deadline I/O scheduler should be used for all disks/LUNs mapped into the KVM guest.

Processor C-states (intel_idle.max_cstate=1 processor.max_cstate=1)

The processor will attempt to save power when idle by switching to a lower power state. Unfortunately this incurs latency when switching in and out of these states. Optimal performance is achieved by limiting the processor to states C0 (normal running state) and C1 (first lower power state). Note that while there is an exit latency associated with C1 states, it is offset on hyperthread-enabled platforms by the fact sibling cores can borrow resources from sibling cores if they are in the C1 state and some CPUs can boost the CPU frequency higher if siblings are in the C1 state.

Hugepages (default_hugepagesz=1 GB hugepagesz=1 GB hugepages=<number of hugepages>)

The use of 1 GiB hugepages is to reduce overhead and contention when the guest is updating its page tables. This requires allocation of 1 GiB hugepages on the host. The number of pages to allocate depends on the memory size of the guest. 1 GiB pages are not pageable by the OS, so they always remain in RAM and therefore the “locked” definition in libvirt XML files is not required. It also important to ensure the order of the hugepage options, specifically the “number of hugepages” option must come after the 1 GiB hugepage size definitions.

The value for “<number of hugepages>” should be calculated by taking the number GiB’s of RAM minus approx. 7% for the Hypervisor OS. For example 2 TiB RAM (2048 GiB) minus 7% are approx. 1900 hugepages.

4 Guest VM XML Configuration

  

This section describes the modifications required to the libvirt XML definition of the Guest VM. The libvirt XML may be edited using the following command:

virsh edit <Guest VM name>

4.1 Create an Initial Guest VM XML

  

Refer to section 9 “Guest Installation” of the SUSE Virtualization Guide (https://documentation.suse.com/sles/12-SP4/html/SLES-all/cha-kvm-inst.html ).

4.2 Global vCPU Configuration

  

Ensure that the following XML elements are configured:

  • domain XML supports “xmlns:qemu” to use qemu commands directly

  • architecture and machine type are set to match the qemu version installed on the Hypervisor

    • for example “2.6” for qemu 2.6 on SUSE Linux Enterprise Server for SAP Applications 12 SP2

  • cpu mode is set to “host-passthrough”

  • the defined qemu CPU command lines necessary for SAP HANA support are used

The following XML example demonstrates how to configure this:

<domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
...
    <os>
       <type arch='x86_64' machine='pc-i440fx-2.6'>hvm</type>
    ...
    </os>
    ...
    <cpu mode='host-passthrough'>
    ...
    </cpu>
    ...
    <qemu:commandline>
      <qemu:arg value='-cpu'/>
      <qemu:arg value='host,migratable=off,+invtsc,l3-cache=on'/>
    </qemu:commandline>
</domain>

Explanation of the critical “l3-cache” option:If a KVM guest has multiple vNUMA nodes it is critical that any L3 CPU cache present on the host be mirrored in the KVM guest. When vCPUs share an L3 cache the Linux kernel scheduler can use an optimized mechanism for enqueuing tasks on vCPUs. Without L3 cache information the guest kernel will always use a more expensive mechanism that involves Inter-Processor Interrupts (IPIs).

Explanation of the “host,migratable-off,+invtsc” options:For best performance, SAP HANA requires the invtsc CPU feature in the KVM guest. However, KVM will remove any non-migratable CPU features from the virtual CPU presented to the KVM guest. This behavior can be overridden by passing the 'migratable=off' and '+invtsc' values to the '-cpu' option.

4.3 vCPU and vNUMA Topology

  

To achieve maximum performance and be supported for use with SAP HANA the KVM guest’s NUMA topology should exactly mirror the host’s NUMA topology and not overcommit memory or CPU resources. This requires pinning virtual CPUs to unique physical CPUs (no virtual CPUs should share the same hyperthread/ physical CPU) and configuring virtual NUMA node relationships for those virtual CPUs.

Note
Note: Physical CPU Core

One physical CPU core (that is 2 hyperthreads) per NUMA node should be left unused by KVM guests so that IOThreads can be pinned there.

Note
Note: Hypervisor Topology

In many use cases it is advisable to map the Hyperthreading topology into the Guest VM as described below since this allows SAP HANA to spread workload threads across many vCPUs. However there maybe workloads which perform better without hyperthreading. In this case only the first physical hyperthread from each core should be mapped into the VM. In the simplified example below that would mean only mapping host processor 0-15 into the VM.

It is important to note that KVM/QEMU uses a static hyperthread sibling CPU APIC ID assignment for virtual CPUs irrespective of the actual physical CPU APIC ID values on the host. For example, assuming that the first hyperthread sibling pair is CPU 0 and CPU 16 on the Hypervisor host, you will need to pin that sibling pair to vCPU 0 and vCPU 1.

Below is a table of a hypothetical configuration for a “4-socket NUMA topology with 4 cores per socket and hyperthreading” server to help understand the above logic. In real world SAP HANA scenarios CPUs will typically have 18+ CPU cores, and will therefore have far more CPUs for the Guest compared to iothreads.

VM Guest          Physical Server    Physical Server   Physical Server
vCPU #            Numa node #        "core id"         processor #
emulator          0                  0                   0
emulator          0                  0                   16
0                 0                  1                   1
1                 0                  1                   17
2                 0                  2                   2
3                 0                  2                   18
4                 0                  3                   3
5                 0                  3                   19
emulpin 1         1                  0                   4
emulpin 4         1                  0                   20
6                 1                  1                   5
7                 1                  1                   21
8                 1                  2                   6
9                 1                  2                   22
10                1                  3                   7
11                1                  3                   23
iohtread 2        2                  0                   8
iothread 5        2                  0                   24
12                2                  1                   9
13                2                  1                   25
14                2                  2                   10
15                2                  2                   26
16                2                  3                   11
17                2                  3                   27
iothread 3        3                  0                   12
iothread 6        3                  0                   28
18                3                  1                   13
19                3                  1                   29
20                3                  2                   14
21                3                  2                   30
22                3                  3                   15
23                3                  3                   31

The following commands can be used to determine the CPU details on the Hypervisor host (see Appendix for an Section 7.2, “Example “lscpu --extended=CPU,SOCKET,CORE” from a Lenovo x3850 x6” and an Section 7.3, “Example “lstopo-no-graphics” from a Lenovo x3850 x6”):

lscpu --extended=CPU,SOCKET,CORE

lstopo-no-graphics

Using the above information the CPU and memory pinning section of the Guest VM XML can be created. Below is an example based on the hypothetical example above.

Make sure to take note of the following configuration points:

  • The “vcpu placement” element lists the total number of vCPUs in the Guest.

  • The “iothreads” element lists the total number of iothreads (6 in this example).

  • The “cputune” element contains the attributes describing the mappings of vCPU, emulator and iothreads to physical CPUs.

  • The “numatune” element contains the attributes to describe distribution of RAM across the virtual NUMA nodes (CPU sockets).

    • The “mode” attribute should be set to “strict”.

    • The appropriate number of nodes should be entered in the “nodeset” and “memnode” attributes. In this example there are 4 sockets, therefore nodeset=0-3 and cellid 0 to 3.

  • The “cpu” element lists:

    • “mode” attribute which should be set to “host-passthrough” for SAP HANA.

    • “topology” attributes to describe the vCPU NUMA topology of the Guest. In this example, 4 sockets, each with 3 cores (see the cpu pinning table) and 2 hyperthreads per core. Set “threads=1” if hyperthreading is not to be used.

    • The attributes of the “numa” elements to describes which vCPU number ranges belong to which NUMA node/socket. Care should be taken since these number ranges are not the same as on the Hypervisor host.

    • In addition, the attributes of the "numa" elements also describe how much RAM should be distributed per NUMA node. In this 4-node example enter 25% (or 1/4) of the entire Guest VM Memory. Also refer to Section 4.5, “Memory Backing” and Section 2.2.1, “Memory Sizing” Memory section of this paper for further details.

<vcpu placement='static'>24</vcpu>
<iothreads>6</iothreads>
  <cputune>
    <vcpupin vcpu='0' cpuset='1'/>
    <vcpupin vcpu='1' cpuset='17'/>
    <vcpupin vcpu='2' cpuset='2'/>
    <vcpupin vcpu='3' cpuset='18'/>
    <vcpupin vcpu='4' cpuset='3'/>
    <vcpupin vcpu='5' cpuset='19'/>

    <vcpupin vcpu='6' cpuset='5'/>
    <vcpupin vcpu='7' cpuset='21'/>
    <vcpupin vcpu='8' cpuset='6'/>
    <vcpupin vcpu='9' cpuset='22'/>
    <vcpupin vcpu='10' cpuset='7'/>
    <vcpupin vcpu='11' cpuset='23'/>

    <vcpupin vcpu='12' cpuset='9'/>
    <vcpupin vcpu='13' cpuset='25'/>
    <vcpupin vcpu='14' cpuset='10'/>
    <vcpupin vcpu='15' cpuset='26'/>
    <vcpupin vcpu='16' cpuset='11'/>
    <vcpupin vcpu='17' cpuset='27'/>

    <vcpupin vcpu='18' cpuset='13'/>
    <vcpupin vcpu='19' cpuset='29'/>
    <vcpupin vcpu='20' cpuset='14'/>
    <vcpupin vcpu='21' cpuset='30'/>
    <vcpupin vcpu='22' cpuset='15'/>
    <vcpupin vcpu='23' cpuset='31'/>

    <emulatorpin cpuset='0,16'/>

    <iothreadpin iothread='1' cpuset='4'/>
    <iothreadpin iothread='2' cpuset='8'/>
    <iothreadpin iothread='3' cpuset='12'/>
    <iothreadpin iothread='4' cpuset='20'/>
    <iothreadpin iothread='5' cpuset='24'/>
    <iothreadpin iothread='6' cpuset='28'/>
  </cputune>

  <numatune>
    <memory mode='strict' nodeset='0-3'/>
    <memnode cellid='0' mode='strict' nodeset='0'/>
    <memnode cellid='1' mode='strict' nodeset='1'/>
    <memnode cellid='2' mode='strict' nodeset='2'/>
    <memnode cellid='3' mode='strict' nodeset='3'/>
  </numatune>

  <cpu mode='host-passthrough'>
    <topology sockets='4' cores='3' threads='2'/>
    <numa>
      <cell id='0' cpus='0-5' memory='<Memory per NUMA node>' unit='KiB'/>
      <cell id='1' cpus='6-11' memory='<Memory per NUMA node>' unit='KiB'/>
      <cell id='2' cpus='12-17' memory='<Memory per NUMA node>' unit='KiB'/>
      <cell id='3' cpus='18-23' memory='<Memory per NUMA node>' unit='KiB'/>
    </numa>
  </cpu>
Note
Note: Memory Unit

The memory unit can be set to GiB to ease the memory computations.

4.4 Storage

  

4.4.1 Storage Configuration for Operating System Volumes

  

The performance of storage where the Operating System is installed is not critical for the performance of SAP HANA, and therefore any KVM supported storage may be used to deploy the Operating system itself.

4.4.2 Storage Configuration for SAP HANA Volumes

  

The Guest VM XML configuration must be based on the underlying storage configuration on the Hypervisor, see section Section 3.3, “Storage Configuration on Hypervisor” for details and adhere the following recommendations:

  • Follow the storage layout recommendations from the appropriate hardware vendors.

  • Only use the KVM virtio “threads” driver

  • Distribute block devices evenly across all available iothreads (see Section 4.4.3, “IOThreads”)

  • Set the following virtio attributes: name='qemu' type='raw' cache='none' io='threads'.

  • Use persistent device names in the Guest VM XML configuration (see example in Section 4.4.3, “IOThreads”).

4.4.3 IOThreads

  

As described in section Section 4.3, “vCPU and vNUMA Topology”, iothreads should be pinned to a set of physical CPUs which are not presented to the Guest VM OS.

Below is an example (device names and bus addresses are configuration dependent) of how to add the iothread options to a virtio device. Note that the iothread numbers should be distributed across the respective virtio devices.

 <disk type='block' device='disk'>
    <driver name='qemu' type='raw' cache='none' io='threads' iothread='1'/>
    <source dev='/dev/disk/by-id/<source device path>'/>
    <target dev='vda' bus='virtio'/>
 </disk>

For further details refer to section 12 “Managing Storage” in the SUSE Virtualization Guide (https://documentation.suse.com/sles/12-SP4/html/SLES-all/cha-libvirt-storage.html)

4.5 Memory Backing

  

Configure the memory size of the Guest VM in KiB and in multiples of 1 GiB (because of the use of 1 GiB hugepages). The max VM size is determined by the total number of 1 GiB hugepages defined on the Hypervisor OS as described in section 4.3.

 <memory unit='KiB'><enter memory size in KiB here></memory>
 <currentMemory unit='KiB'><enter memory size in KiB here></currentMemory>

It is important to use 1 gigabyte hugepages for the guest VM memory backing to achieve optimal performance of the KVM guest. In addition, Kernel Same Page Merging (KSM) should be disabled.

 <memoryBacking>
   <hugepages>
      <page size='1048576' unit='KiB'/>
   </hugepages>
   <nosharepages/>
 </memoryBacking>

4.6 Virtio Random Number Generator (RNG) Device

  

The host /dev/random file should be passed through to QEMU as a source of entropy using the virtio RNG device:

 <rng model='virtio'>
    <backend model='random'>/dev/random</backend>
    <alias name='rng0'/>
 </rng>

5 Guest Operating System

  

5.1 Install SUSE Linux Enterprise Server for SAP Applications Inside the Guest VM

  

Refer to the SUSE Guide “SUSE Linux Enterprise Server for SAP Applications 12 SP2” (https://documentation.suse.com/sles-sap/12-SP2/).

5.2 Guest Operating System Configuration for SAP HANA

  

Install and configure SUSE Linux Enterprise Server for SAP Applications 12 SP2 and SAP HANA as described in:

irqbalance

The irqbalance service should be disabled because it can cause latency issues when the /proc/irq/* files are read. To disable irqbalance run the following command:

systemctl disable irqbalance.service
systemctl stop irqbalance.service

5.3 Guest Operating System Storage Configuration for SAP HANA Volumes

  

  • Follow the storage layout recommendations from the appropriate hardware vendors.

  • Only use LVM (Logical Volume Manager) inside the VM for SAP HANA. Nested LVM is not to be used.

  • Do not configure Multipathing in the guest, but instead on the Hypervisor (see section Section 3.3, “Storage Configuration on Hypervisor”).

6 Administration

  

For a full explanation of administration commands, refer to official SUSE Virtualization documentation such as:

6.1 Useful Commands on the Hypervisor

  

Checking kernel boot options used

cat /proc/cmdline

Checking hugepage status (This command can also be used to monitor the progress of hugepage allocation during VM start)

cat /proc/meminfo |grep Huge

List all VM Guest domains configured on Hypervisor

virsh list --all

Start a VM (Note: VM start times can take some minutes on larger RAM systems, check progress with “ /proc/meminfo | grep Huge ”

virsh start <VM/Guest Domain name>

Shut down a VM

virsh shutdown <VM/Guest Domain name>

Location of VM Guest configuration files

/etc/libvirt/qemu

Location of VM Log files

/var/log/libvirt/qemu

6.2 Useful Commands Inside the VM Guest

  

Checking L3 cache has been enabled in the guest

lscpu | grep L3

Validating Guest and Host CPU Topology

lscpu

7 Examples

  

7.1 Example “lscpu” from a Lenovo x3850 x6

  
# lscpu
Architecture:          x86_64
CPU op-mode(s):        32-bit, 64-bit
Byte Order:            Little Endian
CPU(s):                144
On-line CPU(s) list:   0-143
Thread(s) per core:    2
Core(s) per socket:    18
Socket(s):             4
NUMA node(s):          4
Vendor ID:             GenuineIntel
CPU family:            6
Model:                 63
Model name:            Intel(R) Xeon(R) CPU E7-8880 v3 @ 2.30GHz
Stepping:              4
CPU MHz:               2700.000
CPU max MHz:           3100.0000
CPU min MHz:           1200.0000
BogoMIPS:              4589.07
Virtualization:        VT-x
L1d cache:             32K
L1i cache:             32K
L2 cache:              256K
L3 cache:              46080K
NUMA node0 CPU(s):     0-17,72-89
NUMA node1 CPU(s):     18-35,90-107
NUMA node2 CPU(s):     36-53,108-125
NUMA node3 CPU(s):     54-71,126-143
Flags:                 fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu mce_recovery pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm ida arat epb pln pts dtherm tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm xsaveopt cqm_llc cqm_occup_llc

7.2 Example “lscpu --extended=CPU,SOCKET,CORE” from a Lenovo x3850 x6

  
#  lscpu --extended=CPU,SOCKET,CORE
CPU SOCKET CORE
0   0      0
1   0      1
2   0      2
3   0      3
4   0      4
5   0      5
6   0      6
7   0      7
8   0      8
9   0      9
10  0      10
11  0      11
12  0      12
13  0      13
14  0      14
15  0      15
16  0      16
17  0      17
18  1      18
19  1      19
20  1      20
21  1      21
22  1      22
23  1      23
24  1      24
25  1      25
26  1      26
27  1      27
28  1      28
29  1      29
30  1      30
31  1      31
32  1      32
33  1      33
34  1      34
35  1      35
36  2      36
37  2      37
38  2      38
39  2      39
40  2      40
41  2      41
42  2      42
43  2      43
44  2      44
45  2      45
46  2      46
47  2      47
48  2      48
49  2      49
50  2      50
51  2      51
52  2      52
53  2      53
54  3      54
55  3      55
56  3      56
57  3      57
58  3      58
59  3      59
60  3      60
61  3      61
62  3      62
63  3      63
64  3      64
65  3      65
66  3      66
67  3      67
68  3      68
69  3      69
70  3      70
71  3      71
72  0      0
73  0      1
74  0      2
75  0      3
76  0      4
77  0      5
78  0      6
79  0      7
80  0      8
81  0      9
82  0      10
83  0      11
84  0      12
85  0      13
86  0      14
87  0      15
88  0      16
89  0      17
90  1      18
91  1      19
92  1      20
93  1      21
94  1      22
95  1      23
96  1      24
97  1      25
98  1      26
99  1      27
100 1      28
101 1      29
102 1      30
103 1      31
104 1      32
105 1      33
106 1      34
107 1      35
108 2      36
109 2      37
110 2      38
111 2      39
112 2      40
113 2      41
114 2      42
115 2      43
116 2      44
117 2      45
118 2      46
119 2      47
120 2      48
121 2      49
122 2      50
123 2      51
124 2      52
125 2      53
126 3      54
127 3      55
128 3      56
129 3      57
130 3      58
131 3      59
132 3      60
133 3      61
134 3      62
135 3      63
136 3      64
137 3      65
138 3      66
139 3      67
140 3      68
141 3      69
142 3      70
143 3      71

7.3 Example “lstopo-no-graphics” from a Lenovo x3850 x6

  
# lstopo-no-graphics
Machine (504GB total)
  NUMANode L#0 (P#0 126GB)
    Package L#0 + L3 L#0 (45MB)
      L2 L#0 (256KB) + L1d L#0 (32KB) + L1i L#0 (32KB) + Core L#0
        PU L#0 (P#0)
        PU L#1 (P#72)
      L2 L#1 (256KB) + L1d L#1 (32KB) + L1i L#1 (32KB) + Core L#1
        PU L#2 (P#1)
        PU L#3 (P#73)
      L2 L#2 (256KB) + L1d L#2 (32KB) + L1i L#2 (32KB) + Core L#2
        PU L#4 (P#2)
        PU L#5 (P#74)
      L2 L#3 (256KB) + L1d L#3 (32KB) + L1i L#3 (32KB) + Core L#3
        PU L#6 (P#3)
        PU L#7 (P#75)
      L2 L#4 (256KB) + L1d L#4 (32KB) + L1i L#4 (32KB) + Core L#4
        PU L#8 (P#4)
        PU L#9 (P#76)
      L2 L#5 (256KB) + L1d L#5 (32KB) + L1i L#5 (32KB) + Core L#5
        PU L#10 (P#5)
        PU L#11 (P#77)
      L2 L#6 (256KB) + L1d L#6 (32KB) + L1i L#6 (32KB) + Core L#6
        PU L#12 (P#6)
        PU L#13 (P#78)
      L2 L#7 (256KB) + L1d L#7 (32KB) + L1i L#7 (32KB) + Core L#7
        PU L#14 (P#7)
        PU L#15 (P#79)
      L2 L#8 (256KB) + L1d L#8 (32KB) + L1i L#8 (32KB) + Core L#8
        PU L#16 (P#8)
        PU L#17 (P#80)
      L2 L#9 (256KB) + L1d L#9 (32KB) + L1i L#9 (32KB) + Core L#9
        PU L#18 (P#9)
        PU L#19 (P#81)
      L2 L#10 (256KB) + L1d L#10 (32KB) + L1i L#10 (32KB) + Core L#10
        PU L#20 (P#10)
        PU L#21 (P#82)
      L2 L#11 (256KB) + L1d L#11 (32KB) + L1i L#11 (32KB) + Core L#11
        PU L#22 (P#11)
        PU L#23 (P#83)
      L2 L#12 (256KB) + L1d L#12 (32KB) + L1i L#12 (32KB) + Core L#12
        PU L#24 (P#12)
        PU L#25 (P#84)
      L2 L#13 (256KB) + L1d L#13 (32KB) + L1i L#13 (32KB) + Core L#13
        PU L#26 (P#13)
        PU L#27 (P#85)
      L2 L#14 (256KB) + L1d L#14 (32KB) + L1i L#14 (32KB) + Core L#14
        PU L#28 (P#14)
        PU L#29 (P#86)
      L2 L#15 (256KB) + L1d L#15 (32KB) + L1i L#15 (32KB) + Core L#15
        PU L#30 (P#15)
        PU L#31 (P#87)
      L2 L#16 (256KB) + L1d L#16 (32KB) + L1i L#16 (32KB) + Core L#16
        PU L#32 (P#16)
        PU L#33 (P#88)
      L2 L#17 (256KB) + L1d L#17 (32KB) + L1i L#17 (32KB) + Core L#17
        PU L#34 (P#17)
        PU L#35 (P#89)
    HostBridge L#0
      PCIBridge
        PCI 8086:1521
          Net L#0 "eth0"
        PCI 8086:1521
          Net L#1 "eth1"
        PCI 8086:1521
          Net L#2 "eth2"
        PCI 8086:1521
          Net L#3 "eth3"
  NUMANode L#1 (P#1 126GB)
    Package L#1 + L3 L#1 (45MB)
      L2 L#18 (256KB) + L1d L#18 (32KB) + L1i L#18 (32KB) + Core L#18
        PU L#36 (P#18)
        PU L#37 (P#90)
      L2 L#19 (256KB) + L1d L#19 (32KB) + L1i L#19 (32KB) + Core L#19
        PU L#38 (P#19)
        PU L#39 (P#91)
      L2 L#20 (256KB) + L1d L#20 (32KB) + L1i L#20 (32KB) + Core L#20
        PU L#40 (P#20)
        PU L#41 (P#92)
      L2 L#21 (256KB) + L1d L#21 (32KB) + L1i L#21 (32KB) + Core L#21
        PU L#42 (P#21)
        PU L#43 (P#93)
      L2 L#22 (256KB) + L1d L#22 (32KB) + L1i L#22 (32KB) + Core L#22
        PU L#44 (P#22)
        PU L#45 (P#94)
      L2 L#23 (256KB) + L1d L#23 (32KB) + L1i L#23 (32KB) + Core L#23
        PU L#46 (P#23)
        PU L#47 (P#95)
      L2 L#24 (256KB) + L1d L#24 (32KB) + L1i L#24 (32KB) + Core L#24
        PU L#48 (P#24)
        PU L#49 (P#96)
      L2 L#25 (256KB) + L1d L#25 (32KB) + L1i L#25 (32KB) + Core L#25
        PU L#50 (P#25)
        PU L#51 (P#97)
      L2 L#26 (256KB) + L1d L#26 (32KB) + L1i L#26 (32KB) + Core L#26
        PU L#52 (P#26)
        PU L#53 (P#98)
      L2 L#27 (256KB) + L1d L#27 (32KB) + L1i L#27 (32KB) + Core L#27
        PU L#54 (P#27)
        PU L#55 (P#99)
      L2 L#28 (256KB) + L1d L#28 (32KB) + L1i L#28 (32KB) + Core L#28
        PU L#56 (P#28)
        PU L#57 (P#100)
      L2 L#29 (256KB) + L1d L#29 (32KB) + L1i L#29 (32KB) + Core L#29
        PU L#58 (P#29)
        PU L#59 (P#101)
      L2 L#30 (256KB) + L1d L#30 (32KB) + L1i L#30 (32KB) + Core L#30
        PU L#60 (P#30)
        PU L#61 (P#102)
      L2 L#31 (256KB) + L1d L#31 (32KB) + L1i L#31 (32KB) + Core L#31
        PU L#62 (P#31)
        PU L#63 (P#103)
      L2 L#32 (256KB) + L1d L#32 (32KB) + L1i L#32 (32KB) + Core L#32
        PU L#64 (P#32)
        PU L#65 (P#104)
      L2 L#33 (256KB) + L1d L#33 (32KB) + L1i L#33 (32KB) + Core L#33
        PU L#66 (P#33)
        PU L#67 (P#105)
      L2 L#34 (256KB) + L1d L#34 (32KB) + L1i L#34 (32KB) + Core L#34
        PU L#68 (P#34)
        PU L#69 (P#106)
      L2 L#35 (256KB) + L1d L#35 (32KB) + L1i L#35 (32KB) + Core L#35
        PU L#70 (P#35)
        PU L#71 (P#107)
    HostBridge L#7
    PCIBridge
      PCI 1000:005d
        Block(Disk) L#4 "sda"
        Block(Disk) L#5 "sdb"
        Block(Disk) L#6 "sdc"
        Block(Disk) L#7 "sdd"
        Block(Disk) L#8 "sde"
    NUMANode L#2 (P#2 126GB) + Package L#2 + L3 L#2 (45MB)
    L2 L#36 (256KB) + L1d L#36 (32KB) + L1i L#36 (32KB) + Core L#36
      PU L#72 (P#36)
      PU L#73 (P#108)
    L2 L#37 (256KB) + L1d L#37 (32KB) + L1i L#37 (32KB) + Core L#37
      PU L#74 (P#37)
      PU L#75 (P#109)
    L2 L#38 (256KB) + L1d L#38 (32KB) + L1i L#38 (32KB) + Core L#38
      PU L#76 (P#38)
      PU L#77 (P#110)
    L2 L#39 (256KB) + L1d L#39 (32KB) + L1i L#39 (32KB) + Core L#39
      PU L#78 (P#39)
      PU L#79 (P#111)
    L2 L#40 (256KB) + L1d L#40 (32KB) + L1i L#40 (32KB) + Core L#40
      PU L#80 (P#40)
      PU L#81 (P#112)
    L2 L#41 (256KB) + L1d L#41 (32KB) + L1i L#41 (32KB) + Core L#41
      PU L#82 (P#41)
      PU L#83 (P#113)
    L2 L#42 (256KB) + L1d L#42 (32KB) + L1i L#42 (32KB) + Core L#42
      PU L#84 (P#42)
      PU L#85 (P#114)
    L2 L#43 (256KB) + L1d L#43 (32KB) + L1i L#43 (32KB) + Core L#43
      PU L#86 (P#43)
      PU L#87 (P#115)
    L2 L#44 (256KB) + L1d L#44 (32KB) + L1i L#44 (32KB) + Core L#44
      PU L#88 (P#44)
      PU L#89 (P#116)
    L2 L#45 (256KB) + L1d L#45 (32KB) + L1i L#45 (32KB) + Core L#45
      PU L#90 (P#45)
      PU L#91 (P#117)
    L2 L#46 (256KB) + L1d L#46 (32KB) + L1i L#46 (32KB) + Core L#46
      PU L#92 (P#46)
      PU L#93 (P#118)
    L2 L#47 (256KB) + L1d L#47 (32KB) + L1i L#47 (32KB) + Core L#47
      PU L#94 (P#47)
      PU L#95 (P#119)
    L2 L#48 (256KB) + L1d L#48 (32KB) + L1i L#48 (32KB) + Core L#48
      PU L#96 (P#48)
      PU L#97 (P#120)
    L2 L#49 (256KB) + L1d L#49 (32KB) + L1i L#49 (32KB) + Core L#49
      PU L#98 (P#49)
      PU L#99 (P#121)
    L2 L#50 (256KB) + L1d L#50 (32KB) + L1i L#50 (32KB) + Core L#50
      PU L#100 (P#50)
      PU L#101 (P#122)
    L2 L#51 (256KB) + L1d L#51 (32KB) + L1i L#51 (32KB) + Core L#51
      PU L#102 (P#51)
      PU L#103 (P#123)
    L2 L#52 (256KB) + L1d L#52 (32KB) + L1i L#52 (32KB) + Core L#52
      PU L#104 (P#52)
      PU L#105 (P#124)
    L2 L#53 (256KB) + L1d L#53 (32KB) + L1i L#53 (32KB) + Core L#53
      PU L#106 (P#53)
      PU L#107 (P#125)
    PCIBridge
      PCI 1000:005d
        Block(Disk) L#9 "sdf"
        Block(Disk) L#10 "sdg"
        Block(Disk) L#11 "sdh"
        Block(Disk) L#12 "sdi"
    NUMANode L#3 (P#3 126GB) + Package L#3 + L3 L#3 (45MB)
      L2 L#54 (256KB) + L1d L#54 (32KB) + L1i L#54 (32KB) + Core L#54
        PU L#108 (P#54)
        PU L#109 (P#126)
      L2 L#55 (256KB) + L1d L#55 (32KB) + L1i L#55 (32KB) + Core L#55
        PU L#110 (P#55)
        PU L#111 (P#127)
      L2 L#56 (256KB) + L1d L#56 (32KB) + L1i L#56 (32KB) + Core L#56
        PU L#112 (P#56)
        PU L#113 (P#128)
      L2 L#57 (256KB) + L1d L#57 (32KB) + L1i L#57 (32KB) + Core L#57
        PU L#114 (P#57)
        PU L#115 (P#129)
      L2 L#58 (256KB) + L1d L#58 (32KB) + L1i L#58 (32KB) + Core L#58
        PU L#116 (P#58)
        PU L#117 (P#130)
      L2 L#59 (256KB) + L1d L#59 (32KB) + L1i L#59 (32KB) + Core L#59
        PU L#118 (P#59)
        PU L#119 (P#131)
      L2 L#60 (256KB) + L1d L#60 (32KB) + L1i L#60 (32KB) + Core L#60
        PU L#120 (P#60)
        PU L#121 (P#132)
      L2 L#61 (256KB) + L1d L#61 (32KB) + L1i L#61 (32KB) + Core L#61
        PU L#122 (P#61)
        PU L#123 (P#133)
      L2 L#62 (256KB) + L1d L#62 (32KB) + L1i L#62 (32KB) + Core L#62
        PU L#124 (P#62)
        PU L#125 (P#134)
      L2 L#63 (256KB) + L1d L#63 (32KB) + L1i L#63 (32KB) + Core L#63
        PU L#126 (P#63)
        PU L#127 (P#135)
      L2 L#64 (256KB) + L1d L#64 (32KB) + L1i L#64 (32KB) + Core L#64
        PU L#128 (P#64)
        PU L#129 (P#136)
      L2 L#65 (256KB) + L1d L#65 (32KB) + L1i L#65 (32KB) + Core L#65
        PU L#130 (P#65)
        PU L#131 (P#137)
      L2 L#66 (256KB) + L1d L#66 (32KB) + L1i L#66 (32KB) + Core L#66
        PU L#132 (P#66)
        PU L#133 (P#138)
      L2 L#67 (256KB) + L1d L#67 (32KB) + L1i L#67 (32KB) + Core L#67
        PU L#134 (P#67)
        PU L#135 (P#139)
      L2 L#68 (256KB) + L1d L#68 (32KB) + L1i L#68 (32KB) + Core L#68
        PU L#136 (P#68)
        PU L#137 (P#140)
      L2 L#69 (256KB) + L1d L#69 (32KB) + L1i L#69 (32KB) + Core L#69
        PU L#138 (P#69)
        PU L#139 (P#141)
      L2 L#70 (256KB) + L1d L#70 (32KB) + L1i L#70 (32KB) + Core L#70
        PU L#140 (P#70)
        PU L#141 (P#142)
      L2 L#71 (256KB) + L1d L#71 (32KB) + L1i L#71 (32KB) + Core L#71
        PU L#142 (P#71)
        PU L#143 (P#143)

7.4 Example Guest VM XML Based on the Example Lenovo x3850 x6 Above

  
Warning
Warning: XML Configuration Example

The XML file below is only an example showing the key configurations based on the about command outputs to assist in understanding how to configure the XML. The actual XML configuration must be based on your respective hardware configuration and VM requirements.

Points of interest in this example (refer to the detailed sections of SUSE Best Practices for SAP HANA on KVM - SUSE Linux Enterprise Server for SAP Applications 12 SP2 for a full explanation):

# cat /etc/libvirt/qemu/SUSEKVM.xml
<!--
WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE
OVERWRITTEN AND LOST. Changes to this xml configuration should be made using:
  virsh edit SUSEKVM
or other application using the libvirt API.
-->

<domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
  <name>SUSEKVM</name>
  <uuid>39112135-9cee-4a5e-b36b-eba8757d666e</uuid>
  <memory unit='KiB'>511705088</memory>
  <currentMemory unit='KiB'>511705088</currentMemory>
  <memoryBacking>
    <hugepages/>
      <page size='1048576' unit='KiB'/>
    <nosharepages/>
  </memoryBacking>
  <vcpu placement='static'>136</vcpu>
  <iothreads>5</iothreads>
  <cputune>
    <vcpupin vcpu='0' cpuset='1'/>
    <vcpupin vcpu='1' cpuset='73'/>
    <vcpupin vcpu='2' cpuset='2'/>
    <vcpupin vcpu='3' cpuset='74'/>
    <vcpupin vcpu='4' cpuset='3'/>
    <vcpupin vcpu='5' cpuset='75'/>
    <vcpupin vcpu='6' cpuset='4'/>
    <vcpupin vcpu='7' cpuset='76'/>
    <vcpupin vcpu='8' cpuset='5'/>
    <vcpupin vcpu='9' cpuset='77'/>
    <vcpupin vcpu='10' cpuset='6'/>
    <vcpupin vcpu='11' cpuset='78'/>
    <vcpupin vcpu='12' cpuset='7'/>
    <vcpupin vcpu='13' cpuset='79'/>
    <vcpupin vcpu='14' cpuset='8'/>
    <vcpupin vcpu='15' cpuset='80'/>
    <vcpupin vcpu='16' cpuset='9'/>
    <vcpupin vcpu='17' cpuset='81'/>
    <vcpupin vcpu='18' cpuset='10'/>
    <vcpupin vcpu='19' cpuset='82'/>
    <vcpupin vcpu='20' cpuset='11'/>
    <vcpupin vcpu='21' cpuset='83'/>
    <vcpupin vcpu='22' cpuset='12'/>
    <vcpupin vcpu='23' cpuset='84'/>
    <vcpupin vcpu='24' cpuset='13'/>
    <vcpupin vcpu='25' cpuset='85'/>
    <vcpupin vcpu='26' cpuset='14'/>
    <vcpupin vcpu='27' cpuset='86'/>
    <vcpupin vcpu='28' cpuset='15'/>
    <vcpupin vcpu='29' cpuset='87'/>
    <vcpupin vcpu='30' cpuset='16'/>
    <vcpupin vcpu='31' cpuset='88'/>
    <vcpupin vcpu='32' cpuset='17'/>
    <vcpupin vcpu='33' cpuset='89'/>
    <vcpupin vcpu='34' cpuset='19'/>
    <vcpupin vcpu='35' cpuset='91'/>
    <vcpupin vcpu='36' cpuset='20'/>
    <vcpupin vcpu='37' cpuset='92'/>
    <vcpupin vcpu='38' cpuset='21'/>
    <vcpupin vcpu='39' cpuset='93'/>
    <vcpupin vcpu='40' cpuset='22'/>
    <vcpupin vcpu='41' cpuset='94'/>
    <vcpupin vcpu='42' cpuset='23'/>
    <vcpupin vcpu='43' cpuset='95'/>
    <vcpupin vcpu='44' cpuset='24'/>
    <vcpupin vcpu='45' cpuset='96'/>
    <vcpupin vcpu='46' cpuset='25'/>
    <vcpupin vcpu='47' cpuset='97'/>
    <vcpupin vcpu='48' cpuset='26'/>
    <vcpupin vcpu='49' cpuset='98'/>
    <vcpupin vcpu='50' cpuset='27'/>
    <vcpupin vcpu='51' cpuset='99'/>
    <vcpupin vcpu='52' cpuset='28'/>
    <vcpupin vcpu='53' cpuset='100'/>
    <vcpupin vcpu='54' cpuset='29'/>
    <vcpupin vcpu='55' cpuset='101'/>
    <vcpupin vcpu='56' cpuset='30'/>
    <vcpupin vcpu='57' cpuset='102'/>
    <vcpupin vcpu='58' cpuset='31'/>
    <vcpupin vcpu='59' cpuset='103'/>
    <vcpupin vcpu='60' cpuset='32'/>
    <vcpupin vcpu='61' cpuset='104'/>
    <vcpupin vcpu='62' cpuset='33'/>
    <vcpupin vcpu='63' cpuset='105'/>
    <vcpupin vcpu='64' cpuset='34'/>
    <vcpupin vcpu='65' cpuset='106'/>
    <vcpupin vcpu='66' cpuset='35'/>
    <vcpupin vcpu='67' cpuset='107'/>
    <vcpupin vcpu='68' cpuset='37'/>
    <vcpupin vcpu='69' cpuset='109'/>
    <vcpupin vcpu='70' cpuset='38'/>
    <vcpupin vcpu='71' cpuset='110'/>
    <vcpupin vcpu='72' cpuset='39'/>
    <vcpupin vcpu='73' cpuset='111'/>
    <vcpupin vcpu='74' cpuset='40'/>
    <vcpupin vcpu='75' cpuset='112'/>
    <vcpupin vcpu='76' cpuset='41'/>
    <vcpupin vcpu='77' cpuset='113'/>
    <vcpupin vcpu='78' cpuset='42'/>
    <vcpupin vcpu='79' cpuset='114'/>
    <vcpupin vcpu='80' cpuset='43'/>
    <vcpupin vcpu='81' cpuset='115'/>
    <vcpupin vcpu='82' cpuset='44'/>
    <vcpupin vcpu='83' cpuset='116'/>
    <vcpupin vcpu='84' cpuset='45'/>
    <vcpupin vcpu='85' cpuset='117'/>
    <vcpupin vcpu='86' cpuset='46'/>
    <vcpupin vcpu='87' cpuset='118'/>
    <vcpupin vcpu='88' cpuset='47'/>
    <vcpupin vcpu='89' cpuset='119'/>
    <vcpupin vcpu='90' cpuset='48'/>
    <vcpupin vcpu='91' cpuset='120'/>
    <vcpupin vcpu='92' cpuset='49'/>
    <vcpupin vcpu='93' cpuset='121'/>
    <vcpupin vcpu='94' cpuset='50'/>
    <vcpupin vcpu='95' cpuset='122'/>
    <vcpupin vcpu='96' cpuset='51'/>
    <vcpupin vcpu='97' cpuset='123'/>
    <vcpupin vcpu='98' cpuset='52'/>
    <vcpupin vcpu='99' cpuset='124'/>
    <vcpupin vcpu='100' cpuset='53'/>
    <vcpupin vcpu='101' cpuset='125'/>
    <vcpupin vcpu='102' cpuset='55'/>
    <vcpupin vcpu='103' cpuset='127'/>
    <vcpupin vcpu='104' cpuset='56'/>
    <vcpupin vcpu='105' cpuset='128'/>
    <vcpupin vcpu='106' cpuset='57'/>
    <vcpupin vcpu='107' cpuset='129'/>
    <vcpupin vcpu='108' cpuset='58'/>
    <vcpupin vcpu='109' cpuset='130'/>
    <vcpupin vcpu='110' cpuset='59'/>
    <vcpupin vcpu='111' cpuset='131'/>
    <vcpupin vcpu='112' cpuset='60'/>
    <vcpupin vcpu='113' cpuset='132'/>
    <vcpupin vcpu='114' cpuset='61'/>
    <vcpupin vcpu='115' cpuset='133'/>
    <vcpupin vcpu='116' cpuset='62'/>
    <vcpupin vcpu='117' cpuset='134'/>
    <vcpupin vcpu='118' cpuset='63'/>
    <vcpupin vcpu='119' cpuset='135'/>
    <vcpupin vcpu='120' cpuset='64'/>
    <vcpupin vcpu='121' cpuset='136'/>
    <vcpupin vcpu='122' cpuset='65'/>
    <vcpupin vcpu='123' cpuset='137'/>
    <vcpupin vcpu='124' cpuset='66'/>
    <vcpupin vcpu='125' cpuset='138'/>
    <vcpupin vcpu='126' cpuset='67'/>
    <vcpupin vcpu='127' cpuset='139'/>
    <vcpupin vcpu='128' cpuset='68'/>
    <vcpupin vcpu='129' cpuset='140'/>
    <vcpupin vcpu='130' cpuset='69'/>
    <vcpupin vcpu='131' cpuset='141'/>
    <vcpupin vcpu='132' cpuset='70'/>
    <vcpupin vcpu='133' cpuset='142'/>
    <vcpupin vcpu='134' cpuset='71'/>
    <vcpupin vcpu='135' cpuset='143'/>
    <emulatorpin cpuset='0,54'/>
    <iothreadpin iothread='1' cpuset='72'/>
    <iothreadpin iothread='2' cpuset='18'/>
    <iothreadpin iothread='3' cpuset='36'/>
    <iothreadpin iothread='4' cpuset='90'/>
    <iothreadpin iothread='5' cpuset='108'/>
  </cputune>
  <numatune>
    <memory mode='strict' nodeset='0-3'/>
    <memnode cellid='0' mode='strict' nodeset='0'/>
    <memnode cellid='1' mode='strict' nodeset='1'/>
    <memnode cellid='2' mode='strict' nodeset='2'/>
    <memnode cellid='3' mode='strict' nodeset='3'/>
  </numatune>
  <os>
    <type arch='x86_64' machine='pc-i440fx-2.6'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <vmport state='off'/>
  </features>
  <cpu mode='host-passthrough'>
    <topology sockets='4' cores='17' threads='2'/>
    <numa>
      <cell id='0' cpus='0-33' memory='127926272' unit='KiB'/>
      <cell id='1' cpus='34-66' memory='127926272' unit='KiB'/>
      <cell id='2' cpus='67-101' memory='127926272' unit='KiB'/>
      <cell id='3' cpus='102-135' memory='127926272' unit='KiB'/>
    </numa>
  </cpu>
  <clock offset='utc'>
    <timer name='rtc' tickpolicy='catchup'/>
    <timer name='pit' tickpolicy='delay'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <pm>
    <suspend-to-mem enabled='no'/>
    <suspend-to-disk enabled='no'/>
  </pm>
  <devices>
    <emulator>/usr/bin/qemu-kvm</emulator>
...
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='threads' iothread='1'/>
      <source dev='/dev/disk/by-id/dm-uuid-mpath-xxxxx...'/>
      <target dev='vda' bus='virtio'/>
    </disk>
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='threads' iothread='2'/>
      <source dev='/dev/disk/by-id/dm-uuid-mpath-xxxxx-cd5e'/>
      <target dev='vdf' bus='virtio'/>
    </disk>
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='threads' iothread='3'/>
      <source dev='/dev/disk/by-id/dm-uuid-mpath-xxxxx-cd89'/>
      <target dev='vdg' bus='virtio'/>
    </disk>
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='threads' iothread='4'/>
      <source dev='/dev/disk/by-id/dm-uuid-mpath-xxxxx-c9bb'/>
      <target dev='vdh' bus='virtio'/>
    </disk>
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='threads' iothread='5'/>
      <source dev='/dev/disk/by-id/dm-uuid-mpath-xxxxx-c9e5'/>
      <target dev='vdi' bus='virtio'/>
    </disk>

    <hostdev mode='subsystem' type='pci' managed='yes'>
      <source>
        <address domain='0x0003' bus='0x03' slot='0x00' function='0x0'/>
      </source>
    </hostdev>
...
    <memballoon model='virtio'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </memballoon>
...
    <rng model='virtio'>
      <backend model='random'>/dev/random</backend>
    </rng>
  </devices>
  <qemu:commandline>
    <qemu:arg value='-cpu'/>
    <qemu:arg value='host,migratable=off,+invtsc,l3-cache=on'/>
  </qemu:commandline>
</domain>

8 Additional Information

  

8.1 Resources

  

8.2 Feedback

  

Several feedback channels are available:

Bugs and Enhancement Requests

For services and support options available for your product, refer to http://www.suse.com/support/.

To report bugs for a product component, go to https://scc.suse.com/support/ requests, log in, and select Submit New SR (Service Request).

Report Documentation Bug

To report errors or suggest enhancements for a certain document, use the <> feature at the right side of each section in the online documentation. Provide a concise description of the problem and refer to the respective section number and page (or URL).

Mail

For feedback on the documentation of this product, you can also send a mail to <>. Make sure to include the document title, the product version and the publication date of the documentation.

8.3 Version History

  
VersionPublication DateAuthorComment

0.1

Oct 2017

Lee Martin

Initial version

0.2

Dec 2017

Lee Martin

Pilot Customers

0.3

Jan 2018

Lee Martin

Add storage section

0.4

Feb 2018

Lee Martin

Add sizing section

1.0

Feb 2018

Lee Martin

SAP GA Release for Haswell Single-VM

9 Legal notice

  

Copyright ©2006-2024 SUSE LLC and contributors. All rights reserved.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or (at your option) version 1.3; with the Invariant Section being this copyright notice and license. A copy of the license version 1.2 is included in the section entitled “GNU Free Documentation License”.

SUSE, the SUSE logo and YaST are registered trademarks of SUSE LLC in the United States and other countries. For SUSE trademarks, see http://www.suse.com/company/legal/. Linux is a registered trademark of Linus Torvalds. All other names or trademarks mentioned in this document may be trademarks or registered trademarks of their respective owners.

Documents published as part of the SUSE Best Practices series have been contributed voluntarily by SUSE employees and third parties. They are meant to serve as examples of how particular actions can be performed. They have been compiled with utmost attention to detail. However, this does not guarantee complete accuracy. SUSE cannot verify that actions described in these documents do what is claimed or whether actions described have unintended consequences. SUSE LLC, its affiliates, the authors, and the translators may not be held liable for possible errors or the consequences thereof.

Below we draw your attention to the license under which the articles are published.

10 GNU Free Documentation License

  

Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc. 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

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