Prepare your Linux for your SAP solution with saptune
First of all for what do you need the tool saptune?
- automatically tuning your system without reading tons of SAP notes
- ensures that all your SAP systems configured identically with a central solution
- create your own customized profiles
Why you have to configure all this parameters?
- ensure system performance for your SAP solution like HANA
- run a stable system
- ensure SAP support for certified solution like HANA
SLES for SAP Applications 12 SP2 now ships with the system tuning utility saptune.
In addition to saptune, the package sapconf contains the basic utility sapconf. sapconf also allows tuning for SAP systems but is less comprehensive and offers less granularity than saptune. However, unlike saptune, sapconf is available directly in SUSE Linux Enterprise Server and thus not dependent on using SLES for SAP.
sapconf and saptune both rely on the daemon tuned to set tuning configuration but they use different (though at times very similar) tuning profiles. Therefore, only one of sapconf or saptune can be enabled at a time.
If you have installed your SLES system with the SAP installation wizard the correct profile is already used.
So we have two tools sapconf and saptune:
sapconf: available in SLES11 and SLES12 (without SLES for SAP Applications subscription)
saptune: available since SLES12 SP2 (only with SLES for SAP Applications subscription)
more details about the older tool sapconf in Ulrich Schairer’s blog
How to activate it?
1.List available solutions
saptune solution list
2. Choose a solution
saptune solution apply SOLUTION
3) start daemon
saptune daemon start
disable / enable daemon
systemctl disable tuned systemctl enable tuned
4) check active profile
active profile can be found under
tuned-adm active tuned-adm list
5) Apply single SAP notes
saptune note list
saptune note [ list | verify ]
saptune note [ apply | simulate | verify | customise | revert ] NoteID
You can apply, simulate, verify, customise and revert such notes.
6) Switch between profiles
7) Customize a existing SUSE standard profile
2205917 – SAP HANA DB: Recommended OS settings for SLES 12 / SLES for SAP Applications 12
=> ‘force_latency’ is already set
If you want to add sysctl kernel parameter from other vendors (e.g. VMware for virtualization or NetApp for storage), you can set them in your own profile. Just look into their best practise guides for the recommended parameters.
cp /usr/lib/tuned/sap-hana/tuned.conf /etc/tuned/sap-hana/tuned.conf vi /etc/tuned/sap-hana/tuned.conf [sysctl] net.ipv4.tcp_slow_start_after_idle = 0 [bootloader] cmdline = YOUR_ADDITIONAL_KERNEL_PARAMETERS [script] script = /usr/lib/tuned/sap-hana/script.sh
8. Create your own profile
cp /usr/lib/tuned/sap-hana/tuned.conf /etc/tuned/sap-cust/tuned.conf [sysctl] parameter = value [script] script = /usr/lib/tuned/sap-hana/script.sh
adjust the parameters for your needs – ‘sap-cust’ is the name of the new profile
=> you can see two new profiles ‘sap-test’ and ‘sap-cust’
Delivered SAP Notes
Standard Tuned files
2382421 Optimizing the Network Configuration on HANA- and OS-Level
1868829 Startup Issues Because Number of Active I/O Requests to Queue Exceeds aio-max-nr Limit
2205917 SAP HANA DB: Recommended OS settings for SLES 12 / SLES for SAP Applications 12