saptune 3.1.1 – Do I Need to Update?

This week an update of saptune has reached the repositories and the immanent question is: Do I have to update to 3.1.1?
As you know, the general answer for that kind of question is always “yes”, but lets have a closer look. An increment at the third part of the version number indicates a bug fix, so which bugs do we fix?

/varlog/saptune

On every start saptune v3.1.0 creates the directory /varlog/saptune due to a typo.

This bug is purely cosmetic and has no impact on saptune, but nevertheless can be annoying if you use tab completion. In 3.1.1 this is fixed and an existing directory /varlog gets removed on package installation.

SAP Note 2382421 and Azure

SAP Note 2382421 recommends to set the parameter net.ipv4.tcp_timestamps to 1, which should not be done on Azure environments. With 3.1.1 it won’t.

Restart on package update and IGNORE_RELOAD

If you update the saptune package the tuning gets interrupted shortly when saptune reverts the tuning and reapplies it. This is an undiscovered bug in v3 and never was intended. A package update can contain altered SAP Notes and Solutions and retuning should always be a conscious decision of an admin. 3.1.1 reintroduces the former behavior!

For the majority this should not be a problem. Only very few customers upgrade OS packages with a running SAP application and can suffer from that bug.

As a temporary solution you can add IGNORE_RELOAD="yes" to /etc/sysconfig/saptune before you update to 3.1.1. This prevents the restart during package update.

After the update best set the variable to "no". Why, you ask? By intention a “yes” blocks systemctl reload saptune.service and saptune service restart, but not systemctl restart saptune.service. This behavior can confuse administrators, then restarts belong to normal operation.