How to Tune Systems with saptune

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.

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.

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.

When deleting a note, keep in mind the following:

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.

Keep in mind the following points:

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

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

# saptune note show 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”.

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

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.

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.

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/.

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.

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:

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:

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

# saptune solution show 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.

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”.

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.

To edit a custom SAP Solution, run:

# saptune solution edit 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.