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How to Tune Systems with saptune
SUSE Linux Enterprise Server for SAP applications 16.0

How to Tune Systems with saptune

Publication Date: 24 Oct 2025
WHAT?

Using saptune to tune systems for SAP NetWeaver, SAP HANA/SAP BusinessObjects and SAP S/4HANA applications.

WHY?

saptune simplifies the process of tuning a system for running SAP workloads.

EFFORT

30 minutes of reading time.

GOAL

Learn how to install, configure and use saptune.

REQUIREMENTS

  • A SLES 16 system designated for running SAP workloads

  • A SLES 16 subscription

  • Knowledge of which SAP workload the system is intended to run

1 About saptune

 

saptune is a tool designed for tuning the operating system for running SAP workloads. The tool simplifies the mandatory system tuning as described in various SAP Notes. All the required tuning parameters are added to saptune notes and grouped these notes to solutions representing SAP workloads. This ensures that no parameter is missed, while the saptune service applies all notes and solutions after each system reboot, thus keeping the system reliably tuned at all times.

Important
Important

saptune is used exclusively for tuning the system for SAP workloads, and not the SAP workloads themselves. saptune does not make any changes to SAP configuration files.

2 Installing and enabling saptune

 

Learn how to install, enable, and update saptune.

2.1 Requirements

 

  • A system on which you plan to run SAP workloads. The system must have an active SUSE subscription.

2.2 Installing and enabling saptune

 

Before you install saptune, check if it is already installed on your system. To do this, run the which saptune command. Proceed with installing saptune if the command returns empty output.

To install and enable saptune, proceed as follows:

  1. To install saptune, run the following command: 

    # zypper install saptune

  2. Enable and start the saptune service using the following command: 

    # saptune service enable

2.3 Troubleshooting

 

When installing and updating saptune, pay attention to the zypper output to ensure that installation and updates are performed correctly. The output is also saved in /var/log/zypp/history.

As saptune is installed as a regular RPM package, refer to the Zypper troubleshooting documentation if the saptune installation or update fails.

3 Configuring saptune

 

Learn how to configure saptune after it has been installed.

3.1 Requirements

 

  • A system with saptune installed.

3.2 Configuring saptune

 

Keep in mind that the configure command manages the saptune configuration and not the tuning itself. The command exposes only user-defined changes, and it helps avoid misconfiguration. Configurable options include the color scheme, skipped sysctl files, etc. (refer to man 8 for more info). The command can be used as follows: 

saptune configure PARAMETER VALUE

For example: 

saptune configure COLOR_SCHEME red-noncmpl

To view the saptune configuration file, use the saptune configure show command.

The following command reverts the saptune configuration to its defaults: 

saptune configure reset
Important
Important

Do not edit /etc/sysconfig/saptune directly, and use saptune configure instead.

4 Configuring saptune tuning

 

Learn how to configure saptune tuning.

4.1 Requirements

 

  • A system with saptune installed, configured, and enabled.

4.2 Configuring saptune tuning

 

After installation, saptune starts tuning your system with a minimal base tuning (SAP_Base Solution) as described in the SAP Note 1275776 - Linux: Preparing SLES for SAP environments. However, you should choose the tuning solution that best suits your specific saptune workload.

The easiest way to tune a system is to apply an SAP Solution that matches your installed SAP software. SAP Solutions are a group of SAP Notes that perform the actual tuning. To display all available Solutions and their Notes, run the following command: 

# saptune solution list

saptune recognizes the following tuning SAP Solutions:

  • BOBJ Solution for running SAP BusinessObjects

  • HANA Solution for running an SAP HANA database

  • MAXDB Solution for running an SAP MaxDB database

  • NETWEAVER Solution for running SAP NetWeaver application servers

  • S4HANA-APPSERVER Solution for running SAP S/4HANA Application Servers

  • S4HANA-APP+DB Solution for running both SAP S/4HANA Application Servers and SAP HANA on the same host

  • S4HANA-DBSERVER Solution for running the SAP HANA database of an SAP S/4HANA installation

  • SAP-ASE Solution for running an SAP Adaptive Server Enterprise database. Note that the SAP-ASE Solution and the associated SAP Notes 1805750 and 1680803 are deprecated and removed from saptune 3.2 on SLE 16. The default settings are sufficient for ASE, so no additional tuning is required.

  • NETWEAVER+HANA Solution for running both SAP application servers and SAP HANA on the same host

  • NETWEAVER+MAXDB Solution for running both SAP application servers and MAXDB on the same host

To apply a Solution, run the following command: 

# saptune solution apply SOLUTION

Keep in mind that only one Solution can be applied at a time.

To disable a Solution, use the command below: 

# saptune solution revert SOLUTION

To switch to a different Solution, use the following command: 

# saptune solution change SOLUTION

Alternatively, you can tune the computer according to recommendations from specific SAP Notes. Use the saptune note list to view a list of notes that you can tune for.

To apply a Note, run the following command: 

# saptune note apply NOTE

Reverting a Note can be done as follows: 

# saptune note revert NOTE
Note
Note: Combining optimizations

It is possible to combine Solutions and Notes by reverting Notes from an applied Solution or applying additional ones. However, only one solution can be active at a time. The saptune service restores the combination of Solution and Notes after a service restart or reboot.

In rare cases, Notes can have conflicting options or parameters. Arrange your Notes carefully to avoid conflicts. The last Note always takes priority over conflicting options or parameters of previous notes. In this situation, create your own Solution (see Section 6.2.2, “Creating a new SAP Solution”) or customize the applied Solution (see Section 6.2.1, “Customizing an SAP Solution”).

5 Managing SAP Notes

 

Learn how to manage SAP Notes.

5.1 Requirements

 

  • A system with saptune installed, configured, and enabled.

5.2 Managing SAP Notes

 

The following sections provide information on working with SAP Notes.

An SAP Note configuration contains the OS-specific part of the original SAP Note as completely as possible. A parameter is disabled (it is present in the configuration but has no value) if it does not have a value recommendation, or if saptune cannot safely detect the conditions required to set the correct value. To set a suitable value, read the corresponding SAP Note and customize the Note (see Section 5.2.1, “Customizing an SAP Note”).

5.2.1 Customizing an SAP Note

 

Any SAP Note can be configured using the following command: 

# saptune note customise NOTE

The command opens the default editor with a copy of the Note configuration. Remove everything except the parameters you want to change or disable, as well as the header of the section the parameter belongs to.

To change or set the parameter value, change or add the value of the parameter. To disable a parameter, remove the value, but leave the parameter and the = character. saptune lists parameters, but it does not change or check them for the compliance status. For more information, refer to the saptune-note(5) man page.

This creates a /etc/saptune/override/NOTE file. You can create the file elsewhere and place it in /etc/saptune/override/.

Configuration sections can be conditional. This is called tagging. Refer to the saptune-note(5) for further information.

When you are done customizing a Note, restart the saptune service to apply the changes: 

# saptune service restart

Below is an example of an override file for SAP Note 2382421: 

# Always:
#  - Changing net.ipv4.tcp_max_syn_backlog from 8192 to 65536
#  - Disable net.ipv4.tcp_slow_start_after_idle, because the parameter is tuned elsewhere
#
# On virtual machines additionally:
#  - Change net.ipv4.tcp_syn_retries from 8 to 16

[sysctl]
net.ipv4.tcp_max_syn_backlog = 65536
net.ipv4.tcp_slow_start_after_idle =

[sysctl:virt=vm]
net.ipv4.tcp_max_syn_backlog = 65536
net.ipv4.tcp_slow_start_after_idle =
net.ipv4.tcp_syn_retries = 16

Run the saptune note verify 2382421 command. If the changes have been applied correctly, the output on a virtual machine should be as follows: 

SAPNote, ... | Parameter                          | Expected | Override  | Actual | Compliant
----------------+------------------------------------+----------+-----------+--------+-----------
   ...
   2382421, 47  | net.ipv4.tcp_max_syn_backlog       | 65536    | 65536     | 65536  | yes 
   ...
   2382421, 47  | net.ipv4.tcp_slow_start_after_idle | 0        | untouched | 0      | yes
   2382421, 47  | net.ipv4.tcp_syn_retries           | 16       | 16        | 16     | yes
   ...

On a bare-metal system, the output should be as shown below: 

SAPNote, ... | Parameter                          | Expected  | Override  | Actual | Compliant
----------------+------------------------------------+-----------+-----------+--------+-----------
   ...
   2382421, 47  | net.ipv4.tcp_max_syn_backlog       | 65536     | 65536     | 65536  | yes 
   ...
   2382421, 47  | net.ipv4.tcp_slow_start_after_idle | 0         | untouched | 0      | yes
   2382421, 47  | net.ipv4.tcp_syn_retries           | 8         |           | 8      | yes 
   ...

If changes have not been applied correctly, and you don't see any errors because of the incorrect config file, the Compliant field in the table will display no, and the values in the Actual and Expected fields will differ.

5.2.2 Creating a new SAP Note

 

A new SAP Note can be created using the following command: 

# saptune note create NOTE

The command opens the default editor with a Note configuration template. All the features of saptune are available here. For more information, refer to the saptune-note(5) man page.

This creates a configuration file at /etc/saptune/extra/NOTE.conf. You can also create the file elsewhere and place it in /etc/saptune/extra/.

Configuration sections can be conditional. This is called tagging. Refer to the saptune-note(5) for further information.

5.2.3 Editing a custom SAP Note

 

To edit a custom Note, use the command below: 

# saptune note edit NOTE

The command opens the default editor with the Note configuration. When you are done editing a Note, restart the saptune service to apply the changes. Custom Notes can be customized like shipped Notes.

5.2.4 Deleting an SAP Note or a customization

 

When deleting a note, keep in mind the following:

  • The note can be deleted only if it has not been applied.

  • A confirmation is needed to finish the action.

  • Internal SAP Notes applied by saptune cannot be deleted. Instead, the override file is removed when available.

  • If the Note is already applied, the command is terminated with the message that the note first needs to be reverted before it can be deleted.

The following command deletes a note, including the corresponding override file, if available: 

# saptune note delete test
Note to delete is a customer/vendor specific Note.

5.2.5 Renaming an SAP Note

 

Keep in mind the following points:

  • The note can be renamed only if it has not been applied.

  • A confirmation is needed to finish the action.

  • Internal SAP Notes applied by saptune cannot be renamed.

  • If the Note is already applied, the command is terminated with the information that the Note first needs to be reverted before it can be renamed.

The following command allows renaming a created Note to a new name. If a corresponding override file is available, this file is renamed as well: 

# saptune note rename test test2

5.2.6 Showing the configuration of an SAP Note

 

The configuration of a Note can be listed using the following command: 

# saptune note show NOTE

5.2.7 Verifying an SAP Note

 

To verify the tuning of a Note, use the following command: 

# saptune note verify NOTE

For information about the output of the command and verifying the entire tuning instead of a single Note, refer to Section 7, “Verification and troubleshooting”.

5.2.8 Reverting an SAP Note

 

To revert an SAP Note, run the following command:

# saptune note revert NOTE

This restores all parameters of the SAP Note to their values at the time of application.

To revert everything, use the following command:

# saptune note revert all

5.2.9 Listing all enabled or applied SAP Notes

 

To list all enabled SAP Notes, run the following command: 

# saptune note enabled

To list all applied SAP Notes, run the command below:

# saptune note applied

Both commands are primarily meant for use in scripts.

6 Managing SAP Solutions

 

Learn how to manage SAP Solutions.

6.1 Requirements

 

  • A system with saptune installed, configured, and enabled.

6.2 Managing SAP Solutions

 

This chapter explains how to work with SAP Solutions.

An SAP Solution is a combination of SAP Note configurations grouped logically. It generally represents an SAP product or combination. Applying an SAP Solution effectively applies all SAP Note configurations listed in it. Instructions for listing and setting a solution are provided in Section 4.2, “Configuring saptune tuning”.

6.2.1 Customizing an SAP Solution

 

An SAP Solution can be customized using the following command:

# saptune solution customise SOLUTION

The command opens the default editor (defined in the environment variable EDITOR) with a copy of the Solution configuration. Change the Note list for the architecture to your liking. For more information, refer to the saptune-note(5) man page.

This creates an override file /etc/saptune/override/SOLUTION.sol. It is possible to create the file elsewhere and place it in /etc/saptune/override/.

When you are done customizing an SAP Solution, restart the saptune service to apply the changes.

6.2.2 Creating a new SAP Solution

 

To create a new SAP Solution, run the following command:

# saptune solution create SOLUTION

The command opens the default editor (defined in the environment variable EDITOR) with a Solution configuration template. Fill in the template.

This creates a Solution configuration file /etc/saptune/extra/SOLUTION.sol. You can create the file elsewhere and place it in /etc/saptune/extra/.

6.2.3 Editing a custom SAP Solution

 

To edit a custom SAP Solution, use the following command: 

# saptune solution edit SOLUTION

The command opens the default editor (defined in the environment variable EDITOR) with the Solution configuration.

When you are done editing an SAP Solution, restart the saptune service to apply the changes.

Custom Solutions can be customized like shipped Solutions.

6.2.4 Deleting an SAP Solution

 

The following command deletes a created Solution (in this example, myHANA), including the corresponding override file or the override file of a shipped Solution, if available: 

# saptune solution delete myHANA

Solution to delete is a customer/vendor specific Solution.
Do you really want to delete this Solution 'myHANA'? [y/n]: y

The SAP Solution may not be applied at the time of deletion. Keep in mind the following:

  • A confirmation is required to finish the action.

  • SAP Solutions shipped with saptune cannot be deleted. Only the override file is removed, if available.

  • If the SAP Solution is already applied, the command is terminated with the information that the SAP Solution first needs to be reverted before it can be deleted.

6.2.5 Renaming an SAP Solution

 

To rename an SAP Solution, run the following command:

# saptune solution rename myHANA myHANA2

Solution to rename is a customer/vendor specific Solution.
Do you really want to rename this Solution 'myHANA' to the new name 'myHANA2'? [y/n]:

The SAP Solution may not be applied at this time. Keep in mind the following points:

  • A confirmation is needed to finish the action.

  • SAP Solutions shipped by saptune cannot be renamed.

  • If the SAP Solution is already applied, the command will be terminated with the information that the SAP Solution first needs to be reverted before it can be renamed.

6.2.6 Showing the configuration of an SAP Solution

 

To list the configuration of an SAP Solution, run the following command:

# saptune solution show SOLUTION

6.2.7 Switching to another SAP Solution

 

You can switch to a different solution using the saptune solution change SOLUTION command.

Keep in mind that internally the current solution is reverted first, and then the new solution is applied. If you have additional notes configured, the order is not preserved.

If the same solution is already applied, no action is taken. Otherwise the current solution gets reverted and the new one applied. The command prompts for confirmation before making the change. This can be disabled by adding the --force option.

6.2.8 Verifying an SAP Solution

 

To verify the tuning of a Solution, use the following command: 

# saptune solution verify SOLUTION

For information about the output of the verify command and how to verify the entire tuning instead of a single Solution, refer to Section 7, “Verification and troubleshooting”.

6.2.9 Reverting an SAP Solution

 

To revert an SAP Solution, run the following command:

# saptune solution revert SOLUTION

The SAP Solution must be applied. This reverts all SAP Notes parts of the SAP Solution that are still applied.

6.2.10 Editing a custom SAP Solution

 

To edit a custom SAP Solution, run:

# saptune solution edit SOLUTION

6.2.11 Listing an enabled/applied SAP Solution

 

To list an enabled SAP Solution, run:

# saptune solution enabled

To list an applied SAP Solution, run:

# saptune solution applied

If SAP Notes from an applied SAP Solution have been reverted, the string (partial) has been added to the solution name.

Both commands are primarily meant for use in scripts.

7 Verification and troubleshooting

 

This chapter explains how to verify SAP Notes and troubleshoot saptune.

7.1 Requirements

 

  • A system with saptune installed, configured, and enabled.

7.2 Verification and troubleshooting

 

To see the current status of saptune, run the following command:

# saptune status

The output contains the following:

  • status of the saptune, sapconf, and tuned services

  • version of the package and running saptune

  • details about configured SAP Solutions and SAP Notes

  • details about staging

  • status of the systemd system state

  • virtualization environment (new in saptune version 3.1)

  • tuning compliance (new in saptune version 3.1)

To analyze your saptune installation, run: 

# saptune check

This command performs the following checks:

  • check for mandatory or obsolete configuration files

  • check for RPM leftovers

  • check if the systemd system state is degraded and list failed units

  • check the status of the sapconf, saptune and tuned services

Note
Note

If saptune check warns about a degraded systemd system status, in most cases it has no impact on saptune. However, failed services require troubleshooting.

The command does not check the tuning itself. To check the tuning, use the command below: 

# saptune note verify
Note
Note

If saptune note verify is called without specifying a Note, it verifies all enabled Notes. To verify the currently applied Notes, use the saptune note verify applied or saptune verify applied commands. Normally, enabled Notes are also applied, except when the system has been rebooted without an enabled saptune.service.

The saptune note verify command prints a table with all applied Notes, including the following:

  • SAP Note and version

  • the parameter

  • the expected value of the parameter

  • the value from an Override if one exists

  • the current system value

  • the compliance status of the parameter

The last line contains the overall compliance status of the entire tuning.

Note
Note

Some parameters of shipped Notes are disabled, meaning they have empty values in the Expected column. In such cases, the SAP Note does not contain a concrete recommendation or saptune cannot detect the conditions for a recommendation. Read the SAP Note and set the value manually by customizing the Note (See Section 5.2.1, “Customizing an SAP Note”).

If the parameters are not compliant, read the footnote if it exists. For some tunings, equivalent parameters exist, for example:

  • grub:intel_idle.max_cstate covered by force_latency

  • grub:processor.max_cstate covered by force_latency

  • grub:numa_balancing covered by kernel.numa_balancing

  • grub:transparent_hugepage covered by THP

A restart of the saptune service fixes the problems, except in the case of non-compliant packages (parameter starts with rpm:) or GRUB entries (parameter starts with grub:). saptune does not install, uninstall or upgrade packages, and it never changes the boot loader.

A typical problem is the sysctl parameters that are handled by saptune and sysctl. A footnote in the parameter's compliance column indicates if it is also present in one of the sysctl configuration files. Remove the parameter from the sysctl configuration or disable the parameter in saptune to fix the problem.

Always investigate the cause of the changed tuning and fix it. If saptune does not tune certain parameters, you can revert the Note or just disable parameters via an Override.

8 saptune machine-readable output

 

Overview of saptune's machine-readable output in the JSON format.

8.1 Machine-readable output

 

saptune supports machine-readable output (JSON) for the following commands:

  • saptune [service] status

  • saptune note list|verify|enabled|applied

  • saptune solution list|verify|enabled|applied

  • saptune status

  • saptune version

  • saptune check

The machine-readable output makes it possible to integrate saptune into scripts and configuration management solutions.

To generate JSON output, add --format json as the first option, for example: 

> saptune --format json note applied | jq
{
"$schema": "file:///usr/share/saptune/schemas/1.0/saptune_note_applied.schema.json",
"publish time": "2023-08-29 17:05:45.627",
"argv": "saptune --format json note applied",
"pid": 1538,
"command": "note applied",
"exit code": 0,
"result": {
    "Notes applied": [
    "941735",
    "1771258",
    "1980196",
    "2578899",
    "2684254",
    "2382421",
    "2534844",
    "2993054",
    "1656250"
    ]
},
"messages": []
}

If a command does not yet support JSON output, the command fails with the result block set to "implemented": false: 

[+]
> saptune --format json staging status | jq
{
"$schema": "file:///usr/share/saptune/schemas/1.0/saptune_staging_status.schema.json",
"publish time": "2023-08-29 17:08:16.708",
"argv": "saptune --format json staging status",
"pid": 1653,
"command": "staging status",
"exit code": 1,
"result": {
    "implemented": false
},
"messages": []
}

9 saptune staging

 

Learn how to use staging with saptune

9.1 Requirements

 

  • A system with saptune installed, configured, and enabled.

9.2 Staging

 

It is possible that a new saptune package can contain both binary changes (for example, bug fixes) and new or altered SAP Notes and SAP Solutions. In certain situations, it is preferable to deploy bug fixes and new features while leaving modifications to the system configuration out.

With staging enabled, SAP Note and SAP Solution changes in a package update are not activated immediately. They are placed in a staging area, which can be reviewed and released later.

Important
Important

With the current implementation, a package update overwrites the staging if staging is enabled.

Staging is disabled by default, and it can be enabled with the following command:

# saptune staging enable

From that point, SAP Note and SAP Solution changes shipped by a saptune package are put in the staging area. To view the staging area, run:

# saptune staging list

You can print a tabular overview of the differences between the SAP Note and SAP Solution in the staging and working area with the following command:

# saptune staging diff [NOTE...|SOLUTION...|all]

After reviewing the differences, you can perform an analysis to see if a release has potential issues or requires additional steps. To do this, run the following command: 

# saptune staging analysis [NOTE...|SOLUTION...|all]

To release an SAP Note or an SAP Solution from the staging area, use the command as follows: 

# saptune staging [--force|--dry-run] [NOTE..|SOLUTION...|all]

The command presents an analysis (see saptune staging analysis) and carries out the release after asking for confirmation.

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You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

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You may add a section Entitled "Endorsements", provided it contains nothing but endorsements of your Modified Version by various parties--for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

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The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled "History" in the various original documents, forming one section Entitled "History"; likewise combine any sections Entitled "Acknowledgements", and any sections Entitled "Dedications". You must delete all sections Entitled "Endorsements".

You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

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If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document's Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

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If a section in the Document is Entitled "Acknowledgements", "Dedications", or "History", the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

You may not copy, modify, sublicense, or distribute the Document except as expressly provided for under this License. Any other attempt to copy, modify, sublicense or distribute the Document is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.

The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See https://www.gnu.org/copyleft/.

Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. 

Copyright (c) YEAR YOUR NAME.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.2
or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
A copy of the license is included in the section entitled “GNU
Free Documentation License”.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with...Texts.” line with this: 

with the Invariant Sections being LIST THEIR TITLES, with the
Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.